Perito Moreno glacier is one of the most impressive places I have visited. The map below, with geotagged photos, gives a good idea of what this place looks like. Definitely visit it when you have a chance.
Perito Moreno Glacier at GlobalMotion
Map created using GlobalMotion, the free location wiki, geotagging, geotagged photos
It also shows the power of geotagging. Every photo should be geotagged!
Another one of my favorite places is Arastradero park.
If you are into mountain biking, trail running or hiking, and in the SF Bay Area, definitely visit Arastradero park. It has a nice network of trails.
Arastradero Park at GlobalMotion
Map created using GlobalMotion, the free location wiki