Porto is an exceptionally easy city to visit without a car, and in many ways, having a vehicle is actually a disadvantage due to the extremely narrow, steep, and often pedestrian-only streets in the historic Ribeira district. The city is highly walkable, though you should be prepared for a serious leg workout as the terrain is very hilly. For longer distances, Porto boasts a modern and efficient Metro do Porto system, which connects the airport directly to the city center and crosses the iconic Dom Luís I Bridge to the Gaia side. There is also an extensive network of buses and vintage trams that add a touch of historical charm to your commute. To cross the Douro River, you can walk across the bridge's upper or lower decks, or take a water taxi. For those who want to avoid the steep climbs, the Funicular dos Guindais provides a quick, scenic ride from the riverside up to the Batalha area. If you plan on taking day trips to the Douro Valley or nearby towns like Braga and Guimarães, the CP (Comboios de Portugal) train system is reliable and affordable, departing regularly from the stunning, tile-covered São Bento Station, making a rental car completely unnecessary for the average tourist.