diff --git a/src/dls_utilpack/visit.py b/src/dls_utilpack/visit.py
index 2ef9f91..3367596 100644
--- a/src/dls_utilpack/visit.py
+++ b/src/dls_utilpack/visit.py
@@ -63,6 +63,6 @@ def get_xchem_directory(parent, visit):
     full_path = Path(parent) / subdirectory
 
     if not full_path.is_dir():
-        raise RuntimeError(f"the visit directory {str(full_path)} does not exist")
+        raise VisitNotFound(f"the visit directory {str(full_path)} does not exist")
 
     return str(full_path)
diff --git a/tests/test_visit.py b/tests/test_visit.py
index 443002d..df2aaf3 100644
--- a/tests/test_visit.py
+++ b/tests/test_visit.py
@@ -3,7 +3,11 @@
 
 import pytest
 
-from dls_utilpack.visit import get_xchem_directory, get_xchem_subdirectory
+from dls_utilpack.visit import (
+    VisitNotFound,
+    get_xchem_directory,
+    get_xchem_subdirectory,
+)
 
 # Base class for the tester.
 from tests.base_tester import BaseTester
@@ -59,6 +63,6 @@ async def _main_coroutine(
         assert get_xchem_directory(str(parent), "aa12345-1") == str(full_path)
 
         # Check invalid directory.
-        with pytest.raises(RuntimeError) as excinfo:
+        with pytest.raises(VisitNotFound) as excinfo:
             get_xchem_directory("something", "aa12345-1")
         assert "does not exist" in str(excinfo.value)