To discover the top landmarks around the globe, Facebook aggregated check-ins via its site and third-party apps using the Facebook API. The data dates back to August 2010 when check-ins were first launched.
Some of the interesting facts Facebook uncovered related to check-ins via the site were that sports stadiums and arenas were some of the most popular venues in the world (7 of the number-1-ranked landmarks across the top 25 most social cities were stadiums or arenas); public areas including squares, avenues and parks were second on the list of the most popular check-in destinations (6 out of 25); and cities with warmer climates had more outdoor check-ins than their colder counterparts.
We've reproduced the top 25 here - how many have you checked into? Which would you most like to visit?