diff --git a/src/stan/lang/generator/generate_catch_throw_located.hpp b/src/stan/lang/generator/generate_catch_throw_located.hpp
index b5ad023f5f3..4841e6ceb4c 100644
--- a/src/stan/lang/generator/generate_catch_throw_located.hpp
+++ b/src/stan/lang/generator/generate_catch_throw_located.hpp
@@ -21,7 +21,7 @@ void generate_catch_throw_located(int indent, std::ostream& o) {
   generate_indent(indent, o);
   o << "} catch (const std::exception& e) {" << EOL;
   generate_indent(indent + 1, o);
-  o << "stan::lang::rethrow_located(e, current_statement_begin__"
+  o << "stan::model::rethrow_located(e, current_statement_begin__"
     << ", prog_reader__());" << EOL;
   generate_comment("Next line prevents compiler griping about no return",
                    indent + 1, o);
diff --git a/src/stan/lang/generator/generate_transform_inits_method.hpp b/src/stan/lang/generator/generate_transform_inits_method.hpp
index 401af8cba13..404ee7db8e1 100644
--- a/src/stan/lang/generator/generate_transform_inits_method.hpp
+++ b/src/stan/lang/generator/generate_transform_inits_method.hpp
@@ -110,7 +110,7 @@ void generate_transform_inits_method(const std::vector<block_var_decl>& vs,
     generate_indent(indent, o);
     o << "if (!(context__.contains_r(\"" << var_name << "\")))" << EOL;
     generate_indent(indent + 1, o);
-    o << "stan::lang::rethrow_located("
+    o << "stan::model::rethrow_located("
       << "std::runtime_error(std::string(\"Variable " << var_name
       << " missing\")), current_statement_begin__, prog_reader__());" << EOL;
     // init context position
@@ -157,7 +157,7 @@ void generate_transform_inits_method(const std::vector<block_var_decl>& vs,
     generate_indent(indent + vtype.array_dims(), o);
     o << "} catch (const std::exception& e) {" << EOL;
     generate_indent(indent + vtype.array_dims() + 1, o);
-    o << "stan::lang::rethrow_located("
+    o << "stan::model::rethrow_located("
       << "std::runtime_error(std::string(\"Error transforming variable "
       << var_name
       << ": \") + e.what()), current_statement_begin__, prog_reader__());"
diff --git a/src/stan/lang/generator/generate_validate_tparam_inits.hpp b/src/stan/lang/generator/generate_validate_tparam_inits.hpp
index 2186d98e7ae..e2a103544f8 100644
--- a/src/stan/lang/generator/generate_validate_tparam_inits.hpp
+++ b/src/stan/lang/generator/generate_validate_tparam_inits.hpp
@@ -47,7 +47,7 @@ void generate_validate_tparam_inits(const block_var_decl decl, int indent,
   o << ";" << EOL;
 
   generate_indent(indent + decl.bare_type().num_dims() + 1, o);
-  o << "stan::lang::rethrow_located("
+  o << "stan::model::rethrow_located("
     << "std::runtime_error(std::string(\"Error initializing variable "
     << decl.name()
     << ": \") + msg__.str()), current_statement_begin__, prog_reader__());"
diff --git a/src/stan/model/model_header.hpp b/src/stan/model/model_header.hpp
index f99f38cfb0e..b8afa0162ea 100644
--- a/src/stan/model/model_header.hpp
+++ b/src/stan/model/model_header.hpp
@@ -8,7 +8,7 @@
 #include <stan/io/reader.hpp>
 #include <stan/io/writer.hpp>
 
-#include <stan/lang/rethrow_located.hpp>
+#include <stan/model/rethrow_located.hpp>
 #include <stan/model/model_base.hpp>
 #include <stan/model/model_base_crtp.hpp>
 #include <stan/model/prob_grad.hpp>
diff --git a/src/stan/lang/rethrow_located.hpp b/src/stan/model/rethrow_located.hpp
similarity index 81%
rename from src/stan/lang/rethrow_located.hpp
rename to src/stan/model/rethrow_located.hpp
index 9f63f5cb224..9f68993d689 100644
--- a/src/stan/lang/rethrow_located.hpp
+++ b/src/stan/model/rethrow_located.hpp
@@ -1,5 +1,5 @@
-#ifndef STAN_LANG_RETHROW_LOCATED_HPP
-#define STAN_LANG_RETHROW_LOCATED_HPP
+#ifndef STAN_MODEL_RETHROW_LOCATED_HPP
+#define STAN_MODEL_RETHROW_LOCATED_HPP
 
 #include <stan/io/program_reader.hpp>
 #include <exception>
@@ -12,7 +12,7 @@
 
 namespace stan {
 
-namespace lang {
+namespace model {
 
 /**
  * Returns true if the specified exception can be dynamically
@@ -161,8 +161,37 @@ inline void rethrow_located(const std::exception& e, int line,
   rethrow_located(e, s);
 }
 
-}  // namespace lang
+}  // namespace model
 
+namespace lang {
+/**
+ * Rethrow an exception of type specified by the dynamic type of
+ * the specified exception, adding the specified source file location to
+ * the specified exception's message.
+ *
+ * @param[in] e original exception
+ * @param[in] location string representing the source file location
+ */
+inline void rethrow_located(const std::exception& e, std::string location) {
+  stan::model::rethrow_located(e, location);
+}
+
+/**
+ * Rethrow an exception of type specified by the dynamic type of
+ * the specified exception, adding the specified line number to
+ * the specified exception's message.
+ *
+ * @param[in] e original exception
+ * @param[in] line line number in Stan source program where
+ *   exception originated
+ * @param[in] reader trace of how program was included from files
+ */
+inline void rethrow_located(const std::exception& e, int line,
+                            const io::program_reader& reader
+                            = stan::io::program_reader()) {
+  stan::model::rethrow_located(e, line, reader);
+}
+}  // namespace lang
 }  // namespace stan
 
 #endif
diff --git a/src/stan/model/standalone_functions_header.hpp b/src/stan/model/standalone_functions_header.hpp
index 296cee2afce..025fe255e17 100644
--- a/src/stan/model/standalone_functions_header.hpp
+++ b/src/stan/model/standalone_functions_header.hpp
@@ -5,7 +5,7 @@
 
 #include <boost/random/additive_combine.hpp>
 #include <stan/io/program_reader.hpp>
-#include <stan/lang/rethrow_located.hpp>
+#include <stan/model/rethrow_located.hpp>
 #include <stan/model/indexing.hpp>
 
 #include <cmath>
diff --git a/src/test/unit/lang/generator/cholesky_factor_cov_var_test.cpp b/src/test/unit/lang/generator/cholesky_factor_cov_var_test.cpp
index 49bc84dcae1..4027c3708d8 100644
--- a/src/test/unit/lang/generator/cholesky_factor_cov_var_test.cpp
+++ b/src/test/unit/lang/generator/cholesky_factor_cov_var_test.cpp
@@ -227,7 +227,7 @@ TEST(lang, params_block_var_hpp_xform_inits) {
       "        current_statement_begin__ = 2;\n"
       "        if (!(context__.contains_r(\"cfcov_54\")))\n"
       "            "
-      "stan::lang::rethrow_located(std::runtime_error(std::string(\"Variable "
+      "stan::model::rethrow_located(std::runtime_error(std::string(\"Variable "
       "cfcov_54 missing\")), current_statement_begin__, prog_reader__());\n"
       "        vals_r__ = context__.vals_r(\"cfcov_54\");\n"
       "        pos__ = 0U;\n"
@@ -249,7 +249,7 @@ TEST(lang, params_block_var_hpp_xform_inits) {
       "            writer__.cholesky_factor_cov_unconstrain(cfcov_54);\n"
       "        } catch (const std::exception& e) {\n"
       "            "
-      "stan::lang::rethrow_located(std::runtime_error(std::string(\"Error "
+      "stan::model::rethrow_located(std::runtime_error(std::string(\"Error "
       "transforming variable cfcov_54: \") + e.what()), "
       "current_statement_begin__, prog_reader__());\n"
       "        }\n");
@@ -259,7 +259,7 @@ TEST(lang, params_block_var_hpp_xform_inits) {
       "        current_statement_begin__ = 3;\n"
       "        if (!(context__.contains_r(\"cfcov_33\")))\n"
       "            "
-      "stan::lang::rethrow_located(std::runtime_error(std::string(\"Variable "
+      "stan::model::rethrow_located(std::runtime_error(std::string(\"Variable "
       "cfcov_33 missing\")), current_statement_begin__, prog_reader__());\n"
       "        vals_r__ = context__.vals_r(\"cfcov_33\");\n"
       "        pos__ = 0U;\n"
@@ -281,7 +281,7 @@ TEST(lang, params_block_var_hpp_xform_inits) {
       "            writer__.cholesky_factor_cov_unconstrain(cfcov_33);\n"
       "        } catch (const std::exception& e) {\n"
       "            "
-      "stan::lang::rethrow_located(std::runtime_error(std::string(\"Error "
+      "stan::model::rethrow_located(std::runtime_error(std::string(\"Error "
       "transforming variable cfcov_33: \") + e.what()), "
       "current_statement_begin__, prog_reader__());\n"
       "        }\n");
@@ -503,7 +503,7 @@ TEST(lang, transformed_params_block_var_hpp_log_prob) {
       "                        msg__ << \"Undefined transformed parameter: "
       "cfcov_54\" << \"(\" << j_1__ << \", \" << j_2__ << \")\";\n"
       "                        "
-      "stan::lang::rethrow_located(std::runtime_error(std::string(\"Error "
+      "stan::model::rethrow_located(std::runtime_error(std::string(\"Error "
       "initializing variable cfcov_54: \") + msg__.str()), "
       "current_statement_begin__, prog_reader__());\n"
       "                    }\n"
@@ -525,7 +525,7 @@ TEST(lang, transformed_params_block_var_hpp_log_prob) {
       "                        msg__ << \"Undefined transformed parameter: "
       "cfcov_33\" << \"(\" << j_1__ << \", \" << j_2__ << \")\";\n"
       "                        "
-      "stan::lang::rethrow_located(std::runtime_error(std::string(\"Error "
+      "stan::model::rethrow_located(std::runtime_error(std::string(\"Error "
       "initializing variable cfcov_33: \") + msg__.str()), "
       "current_statement_begin__, prog_reader__());\n"
       "                    }\n"
diff --git a/src/test/unit/lang/generator/function_var_test.cpp b/src/test/unit/lang/generator/function_var_test.cpp
index 345eca536bb..653b663833d 100644
--- a/src/test/unit/lang/generator/function_var_test.cpp
+++ b/src/test/unit/lang/generator/function_var_test.cpp
@@ -216,7 +216,7 @@ TEST(lang, local_function_args_hpp) {
       "            *pstream__ << std::endl;\n"
       "        }\n"
       "    } catch (const std::exception& e) {\n"
-      "        stan::lang::rethrow_located(e, current_statement_begin__, "
+      "        stan::model::rethrow_located(e, current_statement_begin__, "
       "prog_reader__());\n"
       "        // Next line prevents compiler griping about no return\n"
       "        throw std::runtime_error(\"*** IF YOU SEE THIS, PLEASE REPORT A "
@@ -288,7 +288,7 @@ TEST(lang, local_function_args_hpp) {
       "        current_statement_begin__ = 7;\n"
       "        return stan::math::promote_scalar<fun_return_scalar_t__>(a1);\n"
       "    } catch (const std::exception& e) {\n"
-      "        stan::lang::rethrow_located(e, current_statement_begin__, "
+      "        stan::model::rethrow_located(e, current_statement_begin__, "
       "prog_reader__());\n"
       "        // Next line prevents compiler griping about no return\n"
       "        throw std::runtime_error(\"*** IF YOU SEE THIS, PLEASE REPORT A "
@@ -360,7 +360,7 @@ TEST(lang, local_function_args_hpp) {
       "        current_statement_begin__ = 11;\n"
       "        return stan::math::promote_scalar<fun_return_scalar_t__>(a2);\n"
       "    } catch (const std::exception& e) {\n"
-      "        stan::lang::rethrow_located(e, current_statement_begin__, "
+      "        stan::model::rethrow_located(e, current_statement_begin__, "
       "prog_reader__());\n"
       "        // Next line prevents compiler griping about no return\n"
       "        throw std::runtime_error(\"*** IF YOU SEE THIS, PLEASE REPORT A "
@@ -432,7 +432,7 @@ TEST(lang, local_function_args_hpp) {
       "        current_statement_begin__ = 15;\n"
       "        return stan::math::promote_scalar<fun_return_scalar_t__>(a3);\n"
       "    } catch (const std::exception& e) {\n"
-      "        stan::lang::rethrow_located(e, current_statement_begin__, "
+      "        stan::model::rethrow_located(e, current_statement_begin__, "
       "prog_reader__());\n"
       "        // Next line prevents compiler griping about no return\n"
       "        throw std::runtime_error(\"*** IF YOU SEE THIS, PLEASE REPORT A "
@@ -506,7 +506,7 @@ TEST(lang, local_function_args_hpp) {
       "        current_statement_begin__ = 19;\n"
       "        return stan::math::promote_scalar<fun_return_scalar_t__>(a4);\n"
       "    } catch (const std::exception& e) {\n"
-      "        stan::lang::rethrow_located(e, current_statement_begin__, "
+      "        stan::model::rethrow_located(e, current_statement_begin__, "
       "prog_reader__());\n"
       "        // Next line prevents compiler griping about no return\n"
       "        throw std::runtime_error(\"*** IF YOU SEE THIS, PLEASE REPORT A "
@@ -584,7 +584,7 @@ TEST(lang, local_function_args_hpp) {
       "        current_statement_begin__ = 23;\n"
       "        return stan::math::promote_scalar<fun_return_scalar_t__>(a5);\n"
       "    } catch (const std::exception& e) {\n"
-      "        stan::lang::rethrow_located(e, current_statement_begin__, "
+      "        stan::model::rethrow_located(e, current_statement_begin__, "
       "prog_reader__());\n"
       "        // Next line prevents compiler griping about no return\n"
       "        throw std::runtime_error(\"*** IF YOU SEE THIS, PLEASE REPORT A "
@@ -662,7 +662,7 @@ TEST(lang, local_function_args_hpp) {
       "        current_statement_begin__ = 27;\n"
       "        return stan::math::promote_scalar<fun_return_scalar_t__>(a6);\n"
       "    } catch (const std::exception& e) {\n"
-      "        stan::lang::rethrow_located(e, current_statement_begin__, "
+      "        stan::model::rethrow_located(e, current_statement_begin__, "
       "prog_reader__());\n"
       "        // Next line prevents compiler griping about no return\n"
       "        throw std::runtime_error(\"*** IF YOU SEE THIS, PLEASE REPORT A "
@@ -741,7 +741,7 @@ TEST(lang, local_function_args_hpp) {
       "        current_statement_begin__ = 31;\n"
       "        return stan::math::promote_scalar<fun_return_scalar_t__>(a7);\n"
       "    } catch (const std::exception& e) {\n"
-      "        stan::lang::rethrow_located(e, current_statement_begin__, "
+      "        stan::model::rethrow_located(e, current_statement_begin__, "
       "prog_reader__());\n"
       "        // Next line prevents compiler griping about no return\n"
       "        throw std::runtime_error(\"*** IF YOU SEE THIS, PLEASE REPORT A "
@@ -821,7 +821,7 @@ TEST(lang, local_function_args_hpp) {
       "        current_statement_begin__ = 35;\n"
       "        return stan::math::promote_scalar<fun_return_scalar_t__>(a8);\n"
       "    } catch (const std::exception& e) {\n"
-      "        stan::lang::rethrow_located(e, current_statement_begin__, "
+      "        stan::model::rethrow_located(e, current_statement_begin__, "
       "prog_reader__());\n"
       "        // Next line prevents compiler griping about no return\n"
       "        throw std::runtime_error(\"*** IF YOU SEE THIS, PLEASE REPORT A "
@@ -901,7 +901,7 @@ TEST(lang, local_function_args_hpp) {
       "        current_statement_begin__ = 39;\n"
       "        return stan::math::promote_scalar<fun_return_scalar_t__>(a9);\n"
       "    } catch (const std::exception& e) {\n"
-      "        stan::lang::rethrow_located(e, current_statement_begin__, "
+      "        stan::model::rethrow_located(e, current_statement_begin__, "
       "prog_reader__());\n"
       "        // Next line prevents compiler griping about no return\n"
       "        throw std::runtime_error(\"*** IF YOU SEE THIS, PLEASE REPORT A "
@@ -983,7 +983,7 @@ TEST(lang, local_function_args_hpp) {
       "        current_statement_begin__ = 43;\n"
       "        return stan::math::promote_scalar<fun_return_scalar_t__>(a10);\n"
       "    } catch (const std::exception& e) {\n"
-      "        stan::lang::rethrow_located(e, current_statement_begin__, "
+      "        stan::model::rethrow_located(e, current_statement_begin__, "
       "prog_reader__());\n"
       "        // Next line prevents compiler griping about no return\n"
       "        throw std::runtime_error(\"*** IF YOU SEE THIS, PLEASE REPORT A "
@@ -1067,7 +1067,7 @@ TEST(lang, local_function_args_hpp) {
       "        current_statement_begin__ = 47;\n"
       "        return stan::math::promote_scalar<fun_return_scalar_t__>(a11);\n"
       "    } catch (const std::exception& e) {\n"
-      "        stan::lang::rethrow_located(e, current_statement_begin__, "
+      "        stan::model::rethrow_located(e, current_statement_begin__, "
       "prog_reader__());\n"
       "        // Next line prevents compiler griping about no return\n"
       "        throw std::runtime_error(\"*** IF YOU SEE THIS, PLEASE REPORT A "
@@ -1151,7 +1151,7 @@ TEST(lang, local_function_args_hpp) {
       "        current_statement_begin__ = 51;\n"
       "        return stan::math::promote_scalar<fun_return_scalar_t__>(a12);\n"
       "    } catch (const std::exception& e) {\n"
-      "        stan::lang::rethrow_located(e, current_statement_begin__, "
+      "        stan::model::rethrow_located(e, current_statement_begin__, "
       "prog_reader__());\n"
       "        // Next line prevents compiler griping about no return\n"
       "        throw std::runtime_error(\"*** IF YOU SEE THIS, PLEASE REPORT A "
diff --git a/src/test/unit/lang/generator/multi_dim_var_test.cpp b/src/test/unit/lang/generator/multi_dim_var_test.cpp
index 8c11395e17d..e8a5e6b4174 100644
--- a/src/test/unit/lang/generator/multi_dim_var_test.cpp
+++ b/src/test/unit/lang/generator/multi_dim_var_test.cpp
@@ -168,7 +168,7 @@ TEST(lang, params_block_var_hpp_xform_inits) {
       "        current_statement_begin__ = 2;\n"
       "        if (!(context__.contains_r(\"ar_mat\")))\n"
       "            "
-      "stan::lang::rethrow_located(std::runtime_error(std::string(\"Variable "
+      "stan::model::rethrow_located(std::runtime_error(std::string(\"Variable "
       "ar_mat missing\")), current_statement_begin__, prog_reader__());\n"
       "        vals_r__ = context__.vals_r(\"ar_mat\");\n"
       "        pos__ = 0U;\n"
@@ -209,7 +209,7 @@ TEST(lang, params_block_var_hpp_xform_inits) {
       "ar_mat[i_0__][i_1__]);\n"
       "                } catch (const std::exception& e) {\n"
       "                    "
-      "stan::lang::rethrow_located(std::runtime_error(std::string(\"Error "
+      "stan::model::rethrow_located(std::runtime_error(std::string(\"Error "
       "transforming variable ar_mat: \") + e.what()), "
       "current_statement_begin__, prog_reader__());\n"
       "                }\n"
@@ -413,7 +413,7 @@ TEST(lang, transformed_params_block_var_hpp_log_prob) {
       "parameter: ar_mat\" << \"[\" << k_0__ << \"]\" << \"[\" << k_1__ << "
       "\"]\" << \"(\" << j_1__ << \", \" << j_2__ << \")\";\n"
       "                                "
-      "stan::lang::rethrow_located(std::runtime_error(std::string(\"Error "
+      "stan::model::rethrow_located(std::runtime_error(std::string(\"Error "
       "initializing variable ar_mat: \") + msg__.str()), "
       "current_statement_begin__, prog_reader__());\n"
       "                            }\n"
diff --git a/src/test/unit/lang/generator/prim_var_test.cpp b/src/test/unit/lang/generator/prim_var_test.cpp
index 51be76053ec..2927c0b5434 100644
--- a/src/test/unit/lang/generator/prim_var_test.cpp
+++ b/src/test/unit/lang/generator/prim_var_test.cpp
@@ -269,7 +269,7 @@ TEST(lang, params_block_var_hpp_xform_inits) {
       "        current_statement_begin__ = 2;\n"
       "        if (!(context__.contains_r(\"p2\")))\n"
       "            "
-      "stan::lang::rethrow_located(std::runtime_error(std::string(\"Variable "
+      "stan::model::rethrow_located(std::runtime_error(std::string(\"Variable "
       "p2 missing\")), current_statement_begin__, prog_reader__());\n"
       "        vals_r__ = context__.vals_r(\"p2\");\n"
       "        pos__ = 0U;\n"
@@ -281,7 +281,7 @@ TEST(lang, params_block_var_hpp_xform_inits) {
       "            writer__.scalar_unconstrain(p2);\n"
       "        } catch (const std::exception& e) {\n"
       "            "
-      "stan::lang::rethrow_located(std::runtime_error(std::string(\"Error "
+      "stan::model::rethrow_located(std::runtime_error(std::string(\"Error "
       "transforming variable p2: \") + e.what()), current_statement_begin__, "
       "prog_reader__());\n"
       "        }\n"
@@ -289,7 +289,7 @@ TEST(lang, params_block_var_hpp_xform_inits) {
       "        current_statement_begin__ = 3;\n"
       "        if (!(context__.contains_r(\"ar_p2\")))\n"
       "            "
-      "stan::lang::rethrow_located(std::runtime_error(std::string(\"Variable "
+      "stan::model::rethrow_located(std::runtime_error(std::string(\"Variable "
       "ar_p2 missing\")), current_statement_begin__, prog_reader__());\n"
       "        vals_r__ = context__.vals_r(\"ar_p2\");\n"
       "        pos__ = 0U;\n"
@@ -307,7 +307,7 @@ TEST(lang, params_block_var_hpp_xform_inits) {
       "                writer__.scalar_lub_unconstrain(0, 1, ar_p2[i_0__]);\n"
       "            } catch (const std::exception& e) {\n"
       "                "
-      "stan::lang::rethrow_located(std::runtime_error(std::string(\"Error "
+      "stan::model::rethrow_located(std::runtime_error(std::string(\"Error "
       "transforming variable ar_p2: \") + e.what()), "
       "current_statement_begin__, prog_reader__());\n"
       "            }\n"
@@ -316,7 +316,7 @@ TEST(lang, params_block_var_hpp_xform_inits) {
       "        current_statement_begin__ = 4;\n"
       "        if (!(context__.contains_r(\"ar_p3\")))\n"
       "            "
-      "stan::lang::rethrow_located(std::runtime_error(std::string(\"Variable "
+      "stan::model::rethrow_located(std::runtime_error(std::string(\"Variable "
       "ar_p3 missing\")), current_statement_begin__, prog_reader__());\n"
       "        vals_r__ = context__.vals_r(\"ar_p3\");\n"
       "        pos__ = 0U;\n"
@@ -335,7 +335,7 @@ TEST(lang, params_block_var_hpp_xform_inits) {
       "ar_p3[i_0__]);\n"
       "            } catch (const std::exception& e) {\n"
       "                "
-      "stan::lang::rethrow_located(std::runtime_error(std::string(\"Error "
+      "stan::model::rethrow_located(std::runtime_error(std::string(\"Error "
       "transforming variable ar_p3: \") + e.what()), "
       "current_statement_begin__, prog_reader__());\n"
       "            }\n"
@@ -512,7 +512,7 @@ TEST(lang, transformed_params_block_var_hpp_log_prob) {
       "                std::stringstream msg__;\n"
       "                msg__ << \"Undefined transformed parameter: p2\";\n"
       "                "
-      "stan::lang::rethrow_located(std::runtime_error(std::string(\"Error "
+      "stan::model::rethrow_located(std::runtime_error(std::string(\"Error "
       "initializing variable p2: \") + msg__.str()), "
       "current_statement_begin__, prog_reader__());\n"
       "            }\n"
@@ -524,7 +524,7 @@ TEST(lang, transformed_params_block_var_hpp_log_prob) {
       "                    msg__ << \"Undefined transformed parameter: ar_p2\" "
       "<< \"[\" << k_0__ << \"]\";\n"
       "                    "
-      "stan::lang::rethrow_located(std::runtime_error(std::string(\"Error "
+      "stan::model::rethrow_located(std::runtime_error(std::string(\"Error "
       "initializing variable ar_p2: \") + msg__.str()), "
       "current_statement_begin__, prog_reader__());\n"
       "                }\n"
diff --git a/src/test/unit/lang/rethrow_located_test.cpp b/src/test/unit/model/rethrow_located_test.cpp
similarity index 93%
rename from src/test/unit/lang/rethrow_located_test.cpp
rename to src/test/unit/model/rethrow_located_test.cpp
index f1332246b56..1cb1ebdc196 100644
--- a/src/test/unit/lang/rethrow_located_test.cpp
+++ b/src/test/unit/model/rethrow_located_test.cpp
@@ -1,5 +1,5 @@
 #include <stan/io/program_reader.hpp>
-#include <stan/lang/rethrow_located.hpp>
+#include <stan/model/rethrow_located.hpp>
 #include <gtest/gtest.h>
 
 stan::io::program_reader stub_reader() {
@@ -20,7 +20,7 @@ void test_rethrow_located_2() {
       throw E("foo");
     } catch (const std::exception& e) {
       stan::io::program_reader reader = stub_reader();
-      stan::lang::rethrow_located(e, 5, reader);
+      stan::model::rethrow_located(e, 5, reader);
     }
   } catch (const E2& e) {
     EXPECT_TRUE(std::string(e.what()).find_first_of("5") != std::string::npos);
@@ -45,7 +45,7 @@ void test_rethrow_located_nullary(const std::string& original_type) {
       throw E();
     } catch (const std::exception& e) {
       stan::io::program_reader reader = stub_reader();
-      stan::lang::rethrow_located(e, 5, reader);
+      stan::model::rethrow_located(e, 5, reader);
     }
   } catch (const E& e) {
     EXPECT_TRUE(std::string(e.what()).find_first_of("5") != std::string::npos);
@@ -86,13 +86,13 @@ TEST(langRethrowLocated, allExpected) {
 }
 TEST(langRethrowLocated, locatedException) {
   // tests nested case
-  using stan::lang::located_exception;
+  using stan::model::located_exception;
   try {
     try {
       throw located_exception<located_exception<std::exception> >("foo", "bar");
     } catch (const std::exception& e) {
       stan::io::program_reader reader = stub_reader();
-      stan::lang::rethrow_located(e, 5, reader);
+      stan::model::rethrow_located(e, 5, reader);
     }
   } catch (const std::exception& e) {
     EXPECT_TRUE(std::string(e.what()).find_first_of("foo")