One of the most emblematic and representative neighborhoods of Barcelona is the Barrio Gótico, the Gothic Quarter. This area is very well located and quite accessible from any part of the city.
It encompases what one could call the old part of Barcelona, there you have many monuments of great heritage and historical value, from medieval buildings and squares, to real relics of the Roman period.
One of the most interesting features is that walking only a few minutes one can see buildings and squares of different time periods. The most outstanding building is the Cathedral of Barcelona, one of the lovely Gothic constructions on a central square.