diff --git a/django/contrib/sitemaps/views.py b/django/contrib/sitemaps/views.py
index 948c7bc5c49..ab6b9a6d241 100644
--- a/django/contrib/sitemaps/views.py
+++ b/django/contrib/sitemaps/views.py
@@ -27,14 +27,17 @@ def index(request, sitemaps,
     req_protocol = request.scheme
     req_site = get_current_site(request)
 
-    sites = []
+    sites = []  # all sections' sitemap URLs
     for section, site in sitemaps.items():
+        # For each section label, add links of all pages of its sitemap
+        # (usually generated by the `sitemap` view).
         if callable(site):
             site = site()
         protocol = req_protocol if site.protocol is None else site.protocol
         sitemap_url = reverse(sitemap_url_name, kwargs={'section': section})
         absolute_url = '%s://%s%s' % (protocol, req_site.domain, sitemap_url)
         sites.append(absolute_url)
+        # Add links to all pages of the sitemap.
         for page in range(2, site.paginator.num_pages + 1):
             sites.append('%s?p=%s' % (absolute_url, page))