title: Get URL of page requested that caused a 404
body: <p>How would I get the URL of the page that was requested that caused the 404 error?</p>
  
  <p>For example, I type I go to <a href="http://example.com/path/does/not/exist/index.jsp" rel="noreferrer">http://example.com/path/does/not/exist/index.jsp</a>
  I already have a custom 404 page but how would I go about retrieving the URL mentioned above so that I can display it with a message similar to "The url <a href="http://example.com/path/does/not/exist/index.jsp" rel="noreferrer">http://example.com/path/does/not/exist/index.jsp</a> does not exist"?</p>