Use HTTPS to access Apache resources.
diff --git a/src/site/xdoc/index.xml b/src/site/xdoc/index.xml
index 566ecd2..08d9421 100644
--- a/src/site/xdoc/index.xml
+++ b/src/site/xdoc/index.xml
@@ -90,7 +90,7 @@
         For information on previous releases see the
         <a href="release-history.html">Release History</a>
         , and to download previous releases see the
-        <a href="http://archive.apache.org/dist/commons/testing/">Commons Testing Archive</a>
+        <a href="https://archive.apache.org/dist/commons/testing/">Commons Testing Archive</a>
         .
       </p>
     </section>