Spectacular hilltop villages are a dime a dozen on the Greek islands, but Astypalea, a distant speck in the Dodecanese, has the quintessential sugar-cube capital cascading over a rocky outcrop to a sheltered harbor. The oldest houses are huddled along the cliffs circling the Venetian Querini Castle. Castro Bar is built right into the 15th-century castle walls (which look even more dramatic when illuminated by moonlight). A series of small terraces on different levels, painted in white, burgundy, and blue, all offer stupendous views across the island and what feels like the whole Aegean. The vibe is mellow, and the drinks are strong. Stay until the sun rises out of the sea, a trippy experience you won’t forget.