diff --git a/ops/_private/harness.py b/ops/_private/harness.py
index 92fdeec5a..0726ce5b4 100644
--- a/ops/_private/harness.py
+++ b/ops/_private/harness.py
@@ -316,8 +316,9 @@ def __init__(
         )
 
         warnings.warn(
-            'Harness is deprecated; we recommend using state transition testing '
-            "(previously known as 'Scenario') instead",
+            'Harness is deprecated; we recommend state transition testing '
+            "(previously known as 'Scenario') for charm unit tests instead. See more: "
+            'https://ops.readthedocs.io/en/latest/howto/write-unit-tests-for-a-charm.html',
             PendingDeprecationWarning,
             stacklevel=2,
         )