Lying between the Mediterranean Sea and the Atlantic Ocean, Spain has beautiful shores in spades and is home to two island chains popular with vacationing Europeans. The country offers everything from the dramatic Galician coast to the Canary Islands' impressive dunefields to the hidden azure coves of the Costa Brava and the Balearic Islands. A seaside vacation in Spain is the perfect way to get some vitamin D while absorbing a bit of culture, history, and natural beauty. Here's a look at 15 of the best beaches in Spain, each offering unique experiences to suit all types of travelers. Caló des Moro, Mallorca Stefan Mendelsohn/Getty Images You'll find a tiny slice of paradise on the island of Mallorca at Caló des Moro. This beach measures only about 130 feet long and is a bit hard to find—you'll also have to descend a steep set of stairs to reach it. But if you're able and willing, there's nothing quite like swimming in the clear blue waters of this narrow, isolated cove.…