diff --git a/docs/root/start/quick-start/run-envoy.rst b/docs/root/start/quick-start/run-envoy.rst
index 3d6c7b8c103b..dcdba9bcd5b4 100644
--- a/docs/root/start/quick-start/run-envoy.rst
+++ b/docs/root/start/quick-start/run-envoy.rst
@@ -82,6 +82,9 @@ Run Envoy with the demo configuration
 
 The ``-c`` or ``--config-path`` flag tells Envoy the path to its initial configuration.
 
+Envoy will parse the config file according to the file extension, please see the
+:option:`config path command line option <-c>` for further information.
+
 .. tabs::
 
    .. tab:: System