diff --git a/test/core/CMakeLists.txt b/test/core/CMakeLists.txt
index 2b70482aa..ee0933290 100644
--- a/test/core/CMakeLists.txt
+++ b/test/core/CMakeLists.txt
@@ -41,3 +41,4 @@ add_subdirectory(image_view)
 add_subdirectory(algorithm)
 add_subdirectory(image_processing)
 add_subdirectory(histogram)
+add_subdirectory(io)
diff --git a/test/core/Jamfile b/test/core/Jamfile
index 9305b8762..25156392e 100644
--- a/test/core/Jamfile
+++ b/test/core/Jamfile
@@ -33,3 +33,4 @@ build-project image_view ;
 build-project algorithm ;
 build-project image_processing ;
 build-project histogram ;
+build-project io ;
diff --git a/test/core/io/CMakeLists.txt b/test/core/io/CMakeLists.txt
new file mode 100644
index 000000000..171e35485
--- /dev/null
+++ b/test/core/io/CMakeLists.txt
@@ -0,0 +1,25 @@
+#
+# Copyright (c) 2024 Dirk Stolle
+#
+# Distributed under the Boost Software License, Version 1.0.
+# (See accompanying file LICENSE_1_0.txt or copy at
+# http://www.boost.org/LICENSE_1_0.txt)
+#
+foreach(_name
+  path_spec)
+  set(_test t_core_io_${_name})
+  set(_target test_core_io_${_name})
+
+  add_executable(${_target} "")
+  target_sources(${_target} PRIVATE ${_name}.cpp)
+  target_link_libraries(${_target}
+    PRIVATE
+      gil_compile_options
+      gil_include_directories
+      gil_dependencies)
+  add_test(NAME ${_test} COMMAND ${_target})
+
+  unset(_name)
+  unset(_target)
+  unset(_test)
+endforeach()
diff --git a/test/core/io/Jamfile b/test/core/io/Jamfile
new file mode 100644
index 000000000..f696d7076
--- /dev/null
+++ b/test/core/io/Jamfile
@@ -0,0 +1,13 @@
+# Boost.GIL (Generic Image Library) - tests
+#
+# Copyright (c) 2024 Dirk Stolle
+#
+# Distributed under the Boost Software License, Version 1.0.
+# (See accompanying file LICENSE_1_0.txt or
+# copy at http://www.boost.org/LICENSE_1_0.txt)
+
+import testing ;
+
+compile path_spec.cpp ;
+
+run path_spec.cpp ;
diff --git a/test/core/io/path_spec.cpp b/test/core/io/path_spec.cpp
new file mode 100644
index 000000000..8179512e6
--- /dev/null
+++ b/test/core/io/path_spec.cpp
@@ -0,0 +1,59 @@
+//
+// Copyright 2024 Dirk Stolle
+//
+// Distributed under the Boost Software License, Version 1.0
+// See accompanying file LICENSE_1_0.txt or copy at
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/core/lightweight_test.hpp>
+#include <boost/gil/io/path_spec.hpp>
+#include <cstring>
+#include <locale>
+#include <string>
+
+namespace gil = boost::gil;
+
+void test_convert_to_string_from_wstring()
+{
+    std::wstring const path = L"/some_path/傳/привет/qwerty";
+    std::string const expected = "/some_path/\xE5\x82\xB3/\xD0\xBF\xD1\x80\xD0\xB8\xD0\xB2\xD0\xB5\xD1\x82/qwerty";
+
+    std::string string = gil::detail::convert_to_string(path);
+    BOOST_TEST_EQ( 34, string.size() );
+    BOOST_TEST_EQ( expected, string );
+}
+
+void test_convert_to_native_string_from_wchar_t_ptr()
+{
+    wchar_t const* path = L"/some_path/傳/привет/qwerty";
+    char const* expected = "/some_path/\xE5\x82\xB3/\xD0\xBF\xD1\x80\xD0\xB8\xD0\xB2\xD0\xB5\xD1\x82/qwerty";
+
+    char const* string = gil::detail::convert_to_native_string(path);
+    BOOST_TEST_EQ( 34, strlen(string) );
+    BOOST_TEST_EQ( 0, std::strcmp(expected, string) );
+    delete[] string;
+}
+
+void test_convert_to_native_string_from_wstring()
+{
+    std::wstring const path = L"/some_path/傳/привет/qwerty";
+    char const* expected = "/some_path/\xE5\x82\xB3/\xD0\xBF\xD1\x80\xD0\xB8\xD0\xB2\xD0\xB5\xD1\x82/qwerty";
+
+    char const* string = gil::detail::convert_to_native_string(path);
+    BOOST_TEST_EQ( 34, strlen(string) );
+    BOOST_TEST_EQ( 0, std::strcmp(expected, string) );
+    delete[] string;
+}
+
+int main()
+{
+    // Set global locale to one that uses UTF-8. Could be "en_US.UTF-8" or
+    // "C.UTF-8" or something similar, as long as it exists on the system.
+    std::locale::global(std::locale("C.UTF-8"));
+
+    test_convert_to_string_from_wstring();
+    test_convert_to_native_string_from_wchar_t_ptr();
+    test_convert_to_native_string_from_wstring();
+
+    return boost::report_errors();
+}