A few weeks ago I wrote an article on how to install Subversion and Apache in a Windows environment and another article about how to install those in a Linux environment.
As I was migrating from one server to another, I needed to move my repositories from my Windows machine to my new Linux server. I made no special backup. All I had were the files copied into a pen drive exactly as they were in my previous machine. As I wanted to import the repository files along with the commit history and log, here is what I had to do:

1. Dump the content of your old repository

sudo svnadmin dump /old/repository/path > repository_name.svn_dump

2. Create the new repository

sudo svnadmin create /new/repository/path

3. Import the dump file into your new repository

sudo svnadmin load /new/repository/path < repository_name.svn_dump

Of course you can (must) always check the SVN Book, but I hope that this HOW-TO was useful in saving you folks some googling.
Cheers!