Impressive but somewhat overpriced
Casa Batllo is one of the most popular places to visit in Barcelona and the graceful curves and decorative wrought iron balconies of its facade have become something of an icon for the city of Barcelona. The palatial home was built by modernist and Catalan native son Antoni Gaudi whose able hands led to the creation of many of the city's other iconic landmarks like the Park Guell or the Sagrada Familia.
Casa Batllo was built to echo the forms and colors of the Catalan seashore, a motif easily seen in the spirals of the seashell-esque chandelier in the main salon and the turquoise tiles in the interior patio. Across its four floors and rooftop terrace, visitors are taken through wave-like curved staircases, elegant sitting rooms, and whitewashed arched galleries that recall the Mediterranean fishing villages which dot the coast of Catalonia.
However, is it worth it? Taking into account that the entrance fee is around 20€ (much more than the infinitely more spectacular Sagrada Familia) and the only discounts are for documented students and Catalan residents, I'd say this is one sight which travelers should probably skip. Half the charm of Casa Batllo is its exterior and unless you're an architecture connoisseur or Gaudi fanatic, the visit simply isn't worth the price. If you do decide to visit, make sure to take one of the free audio-guides as they really help add historical and artistic context to the home. If you're looking for a souvenir, you can also take a selfie on the home's trademark central balcony but, at 12€ or so for a printed copy, it's a souvenir I decided to skip.