I'm assuming you mean Rattlesnake Point in the Halton region, Milton being the closest town (north of Hamilton, ON). It's about a 30-45 min drive. Lots of routes there. The place gets rather busy so you better get there early. The Buffalo Crag is also near by. If you're into bouldering, there's always the Niagara Glen which is close to the Niagara Butterfly Conservatory.
Hope that helps.