On a rainy afternoon in Plaza de España Barcelona, one of the best things to do is to visit the Museu Nacional d'Art de Catalunya. Located in the Palau Nacional, this museum houses an extensive collection of Catalan art from the Romanesque period to the mid-20th century. You can explore the various galleries and admire masterpieces by renowned artists such as Salvador Dalí, Joan Miró, and Pablo Picasso. The museum also offers stunning views of the city from its terrace, making it a perfect spot to enjoy the rainy scenery while appreciating art.