Using public transport in Madrid, Spain is hassle-free. It is so simple that it even might not be worth writing an article about. When you reach the metro station at the airport you’ll find vending machines where you can get a smartcard and load tickets for a definite number of trips or days onto it. For tourists there is also a small office where you can buy your ticket from humans.
For tourists zone A + airport is sufficient. When you’ve bought your ticket you just need to validate it when entering a metro station. The network is rather dense and consists of 13 color-coded lines. Smartphone apps calculate the best route and tell you which line you have to take in which direction. The signage underground and acess to the mobile network are extraordinarily good.
Sometimes you might need to use a bus in addition (mostly because it’s fast – on some routes you would have to switch metro trains too often). In that case it is absolutely worth to have a valid smartcard in your pocket – bus drivers only give a maximum change of five Euros. On busses you’ll have to validate your smartcard when entering the vehicle in front. The next stops are shown on a display so that also using this type of public transport is easy.