diff --git a/tests/README.md b/tests/README.md
index 3c65e564ea3..640a59ad912 100644
--- a/tests/README.md
+++ b/tests/README.md
@@ -11,6 +11,13 @@ Make sure that you have enabled building of tests in CMake.
 Some tests require setting up a test environment.
 Below some information about how to set such environment up.
 
+## Docker based environment
+
+The test environment used by the continuous integration system
+is based on Docker and can be reproduced locally by using the
+`.ci/run_tests.sh` script. Run with the --help switch to see
+options.
+
 ## Postgres
 
 Make sure that you have enabled building of postgres test in CMake.