diff --git a/demo/images/index.md b/demo/images/index.md
index 42fb551f..bc234a37 100644
--- a/demo/images/index.md
+++ b/demo/images/index.md
@@ -83,4 +83,11 @@ Start numbering with offset:
 57. foo
 1. bar
 
+<!-- @pg-date 2015-06-12 -->
+## Day 1
+
+You can tag section in the `*.md` files  with `<!-- @pg-date <ISO_DATE> -->`, like: `<!-- @pg-date 2015-06-12 -->` to attach them to a date. 
+Then, if you group by date, they will show up at the assigned day.
+
+That part of the markdown will be removed from the main markdown at the top and shown only at that day.