Update conservation-area.md

Tweaks to documentation-url field guidance

application/templates/pages/guidance/specifications/conservation-area.md

@@ -59,9 +59,23 @@ If you’re providing geometry in a GeoJSON, GML or Geopackage, use the associat
 
 ### documentation-url
 
-The URL of the webpage on the local planning authority website which provides information about the conservation area.
+The URL of the webpage on your website that introduces the document.
 
-Example: `http://www.LPAwebsite.org.uk/data#conservationarea1`
+Each document should be linked to from a documentation webpage that includes a short description of the data and the document you’re linking to. Each article 4 direction should have a unique URL. This means you can create a separate page for each one, or you could list several on one page. If you do that, there must be a separate anchor link (fragment identifier) for each one. 
+
+This means each section of your page should have its own URL. Most publishing systems will allow you to use a hashtag to create the identifiers for each article 4 direction you list - as in the examples shown.
+
+Examples:
+
+One article 4 direction per page:
+
+`http://www.LPAwebsite.org.uk/data/article4directions/smithroad`
+
+More than one article 4 direction per page with an anchor link for each one:
+
+`http://www.LPAwebsite.org.uk/data/article4directions#smithroad`
+
+`http://www.LPAwebsite.org.uk/data/article4directions#broadhousepark`
 
 ### notes