The metro journey from Porto’s city center to the Francisco Sá Carneiro Airport (OPO) typically takes 26 to 28 minutes. You must take Line E (the Purple Line), which runs directly between the Aeroporto station and Estádio do Dragão. If you are starting from the central Trindade hub, the trip is exactly 27 minutes. The metro is one of the most efficient ways to reach the airport, with trains running every 20 to 30 minutes depending on the time of day and whether it is a weekday or weekend. The first train usually departs around 6:00 AM, and the last one around 1:00 AM. You will need an Andante card with a Z4 (Zone 4) fare, which currently costs around €2.00 to €2.25. Because the metro station at the airport is located directly across from the arrivals terminal, it is a very convenient and weather-protected option compared to taking a bus or a taxi, which can be subject to the city's unpredictable traffic congestion.