The capital of the United Arab Emirates, Abu Dhabi is about ninety miles from Dubai, an hour and a half or so by car. If you have extra time in Dubai and you haven’t explored the UAE before, it’s worth the trip out; every emirate in the UAE is remarkably differently (also see Sharja/Aman). There aren’t many mosques that non-Muslims can enter in Dubai (or the region), but the most stunning one, which happens to be open to visitors, is in Abu Dhabi—Sheikh Zayed Mosque, named after the original president of the UAE. An enormous, majestic place of prayer—built with more than 100,000 tons of white marble, to fit 40,000 worshippers—Sheikh Zayed Mosque has eighty-two domes, one thousand pillars, and four crowning minarets. The architecture and design borrows from diverse Islamic styles and includes subtle floral shapes cut with semi-precious stones and sharp, geometric details, that as a whole feel strikingly modern. Visitors can go inside the mosque as long as prayer isn’t in session (check here before you go), where you can see the world’s largest hand-knotted carpet (5,700 square meters that are said to be the work of 1,2000 craftsmen and took over a year to make). The emirate of Abu Dhabi is also home to the world’s fastest roller coaster (Formula Rossa at Ferrari World on Yas Island), and the ambitious (fascinatingly challenged) eco-energy project Masdar City.