Backup and Restore a Subversion Repository

First, here's how back up the repository to a compressed file:

$ svnadmin dump /path/to/repo | gzip > backup.gz

And how to restore it:

$ gunzip -c backup.gz | svnadmin load /path/to/repo

Those commands are meant for UNIX or Linux so you will have to adapt 
them if you are running Windows. It shouldn't be too difficult to do so,
 especially if you are using Cygwin.