2. Kirkland House, Cambridge, MA
You’ll definitely want to schedule your visit to Kirkland House, the legendary birthplace of Facebook, because it’s still a working dorm at Harvard University. Back when Facebook still touted the “the” at the beginning of its name, and Mark Zuckerberg was just hoping to drum up members, it was Kirkland House’s mailing list that supplied his first batch of members. Today, student-led tours of Harvard will happily tell you all about it.