The beautiful thing about the apartment is that its very centric. It's in the middle of El Gotico, where you can find everything you need to see in Barcelona.
Its close to everything. Museums, historic buildings, but also Las Ramblas, the beach, clubs, shopping area, luxury boutiques etc etc.
The apartment is situated about 2 minutes walking from the metro, bus and train stations. The public transport in Barcelona is excellent, easy to use and a cheap way to get yourself around town.