$Page — Getting the URL of a Sites Page

Nothing revolutionary here, just something I needed to find quickly and didn't appear to be obviously apparent, of course it's in the documentation etc., I just figured I'd share it too so that the answer is even easier to find.

Scenario

You're exposing some Visualforce pages over sites, and in one of those pages you want to link to another.

Solution

My first reaction was to use ApexPages.currentPage() in the controller to grab the current URL which I could then modify, but that's not the correct (or simple) approach! All you need is to utilise one of  the Visualforce Global Variables: $Page.

{!$Page.PageName}
<!-- For Example -->
<a href="{!$Page.Page2}">Link to Page 2</a>

Too easy!