The metro is often the fastest way to get around town, although it doesn’t allow you to get your bearings as the aboveground trams do. Two of the four lines that run through the city stop at the Duomo and allow for easy connections to Milan Central Station and neighbourhoods like Porta Romana. Similar to the tram and the bus, it’s possible to purchase tickets on the ATM app, but the QR code doesn’t always easily scan at the metro turnstiles. For that reason, purchase a ticket from one of the machines at the metro station, which offer services in multiple languages. One ride, including transfers, costs 2 euros, and you must have your ticket to enter and exit the metro; once you enter the metro and validate your ticket, you are given 90 minutes to ride on trams and buses, which is helpful if you need to use two forms of transport. You can also purchase tickets over SMS by texting 'ATM' to 48444.