The capital of Spain's Catalonia region is one of Europe's most beautiful and vibrant places. Barcelona is like no other Spanish city; this is most evident in its language (locals speak Catalan, not Castilian Spanish) and in its architecture, a marriage of Gothic spikes and modern curves. Keep your eye out for the unmistakable work of Antoni Gaudi, the city's best known architect.
Barcelona sits between the Collserola mountains and the Mediterranean Sea. The easiest way for visitors to get their bearings is to know that the city is basically divided into two parts. First, there's the old city, which is where the heart of everything -- from museums to shopping and cafes -- is based. Then there's the port area, known as Port Vell, featuring bars, restaurants, shops and an IMAX theater.
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In fact, one of Barcelona's best attributes is that while it seems large and spread out, its neighborhoods are surprisingly walkable and easily accessible by bus, metro or even foot (in comfortable shoes). Don't miss a stroll along La Rambla, replete with produce and flower stands, a historic opera house, live statues, and a thoroughly intriguing open pet market with cages of for-sale lizards, chirping birds and other exotic animals.
Just be sure to rest your feet now and then over a few plates of tapas (which are meant to be shared, but we won't tell) and an ice-cold pitcher of sangria.
Editor's Note: Barcelona is notorious for pickpockets, particularly along La Rambla. Leave valuables in your hotel safe, and carry credit cards and cash in a secure place (ideally in a money belt under your clothes). For more information, see our Money Safety Tips.
--updated by Melissa Paloti and Sarah Schlichter