You could spend a good part of your life wending your way through Mill Valley finding the many steps, paths and lanes which exist. There's a Step, Paths and Lanes Map and now its companion book by Michael O'Shaughnessy. Thanks to KEVIN D1 for posting this and check out his mention of Doug Beyerlein's http://www.publicstairs.com/index_000002.htm where Mill Valley's public stairs of more than 100 steps are listed. We have 24, 8 more than Berkeley. If you click on each staircase's car icon, you can find how to get there from your home.