diff --git a/zerver/lib/events.py b/zerver/lib/events.py
index 86382b572b..dedd77dc09 100644
--- a/zerver/lib/events.py
+++ b/zerver/lib/events.py
@@ -1,3 +1,5 @@
+# See http://zulip.readthedocs.io/en/latest/events-system.html for
+# high-level documentation on how this system works.
 from __future__ import absolute_import
 from __future__ import print_function
 
diff --git a/zerver/tests/test_events.py b/zerver/tests/test_events.py
index fb5d3b47aa..2b3ffbda83 100644
--- a/zerver/tests/test_events.py
+++ b/zerver/tests/test_events.py
@@ -1,4 +1,6 @@
 # -*- coding: utf-8 -*-
+# See http://zulip.readthedocs.io/en/latest/events-system.html for
+# high-level documentation on how this system works.
 from __future__ import absolute_import
 from typing import Any, Callable, Optional
 
diff --git a/zerver/tornado/event_queue.py b/zerver/tornado/event_queue.py
index 4a09a37b1e..496b8fad5e 100644
--- a/zerver/tornado/event_queue.py
+++ b/zerver/tornado/event_queue.py
@@ -1,3 +1,5 @@
+# See http://zulip.readthedocs.io/en/latest/events-system.html for
+# high-level documentation on how this system works.
 from __future__ import absolute_import
 from typing import cast, AbstractSet, Any, Optional, Iterable, Sequence, Mapping, MutableMapping, Callable, Union, Text