La Paz, Bolivia (4/13)

This city high in the Andes (nearly 12,000 feet above sea level) offers five-star accommodation for under $150 per night. The longest and highest cable car network in the world, Mi Teleférico, will get you from place to place as you explore the city. Street food is common and cheap. Acclimatize to the altitude while visiting the Mercado de las Brujas (the Witches’ Market), where you can find handcrafted items alongside folk and herbal remedies, then go skiing on one of the highest slopes in the world.