Former headquarters of the "Textil Algodonera Foundation", an emblematic building of the XIX century of neoclassical style that is a reference in the city of Barcelona. They have an excellent restaurant where you can make a good brunch and a terrace ideal for summer evenings, I usually go to design when I need tranquility and that they treat me with professionalism, ideal also for an informal meeting or a drink with a good friend.
Where the lights come from is the national museum of art in Catalunya. Its an impressive building with great exhibitions and a huge collection of hostoric art. In that area you will also find Mies Van Der Roes house and Caixa forum (Av. Francesc Ferrer i Guàrdia, 6-8).
I only recommend walking around the Barceloneta beach at sunset, there are fewer people and in the fall and spring seasons is very nice to sit on a terrace watching the sea and entertaining yourself with the activities of the area.