Porto, Portugal

The Old Town: The riverfront action across the Douro from the ship is enticing, and you can easily reach that side on foot or by tram, but the Gaia side has plenty to offer. The dining scene is just as good, and the drinking is better because this is where the port wineries have set up their public cellars.

The Sunsets: If you’re in Porto for more than one night, try to check out one sunset from a riverside vantage point and one from shipboard, sailing to the mouth of the harbor.

Port Wine: The most famous port wineries in Portugal have public tasting facilities in Gaia, just a few steps back from the riverbank. They’re also called cellars or caves because most have working storage cellars visitors can tour.

Clerigos Church and Tower: Find this hillside landmark by walking up narrow streets through the heart of old town, and enjoy photo ops all along the way. It’s free to enter the church, and for a few euro, you can access a tiny museum and take the 240 steps to the top of the church tower.

Oenophiles: Even if you don’t love port, which is just too sweet for some people, the other Portuguese wines are delicious, varied, and affordable.

Those Who Love to Walk: This is a great walking city — compact, full of shops and restaurants, and easy to navigate because you can see the bridge and tram from most everywhere.

The Hills Are Alive: This city's hills will eventually tire you out. To get back to your ship, go downhill and cross the bridge.

People Will Try to Sell You Stuff: The riverside across from Gaia draws a noticeable number of hawkers selling trinkets. If it’s late at night or a holiday, Gaia isn't as lively, but it's also less sketchy.