Menorca

Menorca is the Balearic that kept its secret. While Mallorca built resorts and Ibiza built superclubs, its quiet northern sister got itself declared a UNESCO Biosphere Reserve in 1993 and more or less stopped the clock — a low, green island ringed by some of the most beautiful water in the Mediterranean and a 185-kilometre coast path that strings every cove of it together. The south coast hides white-sand calas the colour of a swimming pool; the wild north throws up red cliffs, black sand, and a wind with its own name. Scattered across the middle are stone towers and burial chambers from a Bronze Age culture that built here for two thousand years — including a roofed monument often called the oldest standing building in Europe.

It's also a near-perfect group island. You can cross the whole thing in under an hour, which means one rented villa and a car or two is the entire logistical problem solved: nobody argues about the plan because the plan is a different cove every day. The British ran the place for most of the 1700s and left behind a deep-water harbour, sash windows, a juniper gin, and — depending on which origin myth you believe — mayonnaise. Come in June or September with four or six friends, book the lobster dinner and the Sant Joan beds early, and let the island set the pace. It only has one, and it's slow.