Location-based biggest social networks are Gowalla and Foursquare. But Gowalla is more tourist friendly. You can add trips and pictures. As I see, there was no trips in Estonia in Gowalla until now. This is simple Gowalla Trip of Lahemaa National Park. Enjoy.
Gowalla Trip consists of five spots...
Kolga Mõis
Viinistu Restoran
Käsmu Rand
Vihula Manor Country Club & Spa
Palmse Manor
You need to only check-in to this five spots and Your trip is completed.