Estação da Sé
Category: Transportation
This subway station is located in the "basement" of Praça da Sé ("Sé Square"). It is the biggest and most important station of São Paulo's subway system. It has three floors and it is there that the North-South and East-West lines meet, reason why it is also the most crowded one since it is where people change trains.
http://www.saopaulo.sp.gov.br/ingles/saopaulo/turismo/cap_ptos_se.htm