As of July 2012, FreeBSD uses Subversion (svn) as the primary version control system for storing all of FreeBSD's source code, documentation, and the Ports Collection.
The FreeBSD svn mirror network is still in its early days, and will likely change. Do not count on this list of mirrors being static. In particular, the SSL certificates of the servers will likely change at some point.
In Subversion, URLs are used to designate a repository, taking the form of protocol://hostname/path. Mirrors may support different protocols as specified below. The first component of the path is the FreeBSD repository to access. There are three different repositories, base for the FreeBSD base system source code, ports for the Ports Collection, and doc for documentation. For example, the URL svn://svn0.us-east.FreeBSD.org/ports/head/ specifies the main branch of the ports repository on the svn0.us-east.FreeBSD.org mirror, using the svn protocol.
All mirrors carry all repositories.
The master FreeBSD Subversion server, svn.FreeBSD.org, is publicly accessible, read-only. That may change in the future, so users are encouraged to use one of the official mirrors. To view the FreeBSD Subversion repositories through a browser, use http://svnweb.FreeBSD.org/.