Trullo buildings in Alberobello, Apulia, Italy (© Feng Wei Photography/Getty Images)

If fairy tales had architects, they might've come up with something like Alberobello in Italy. But instead of magic wands, it was limestone, mortar-free masonry, and—according to some theories—a bit of tax evasion that built this town's signature homes: the trulli. These are whitewashed stone houses topped with dry-stacked limestone roofs shaped like upside-down ice cream cones. It's an ancient building technique, and in this case, a clever one. Back in the 14th century, locals were reportedly trying to avoid property taxes by constructing homes that could be quickly dismantled when the king's tax collector came around.