I’m sure you are already very well informed about metro and train, the prices, bus stop and metro map, but I want to explain about zones. Madrid subway or underground and train lines have zones like London tube:
- A1 = City centre
- B1 = Suburbs
- B2 = More suburbs
- B3 = Still suburbs like Alcalá de Henares
- C1 = Towns like El Escorial
- C2 = Mordor
You can travel until B1 zone by metro (metro Norte, metro Sur, metro Este and metro ligero), the rest zones just by train (called RENFE Cercanías). Also you have buses if you like but I’m the kind of person who feels dizzy in a bus and train/metro are timely.