The Metro is an experience. It is like getting into a sauna - the dirtiest, smelliest, most crowded sauna you can imagine. If you can walk - you should probably walk. BUT the metro is only 3 pesos and you can get all the way across the city. If you are traveling at rush hour, there is a women's only section that is quite roomy! The system is huge and built with the most durable materials - a heavy concrete structure with steel details.