Ever since the Romans introduced grapes, wine and the Douro River have flowed seamlessly through Porto’s story.

Port, from upstream vineyards, aged in the vast wine lodges on the opposite shore before shipping in vessels built in Porto shipyards. This winning combination turned Porto into Portugal’s second-largest city.

While there’s plenty to do, no must-see icon requires a visit. Eiffel didn’t build a tower here; he did build a bridge, although not the central city’s eye-catching, double-decker Dom Luis I Bridge. Cross Dom Luis I Bridge to the colorful Vila Nova de Gaia, spilling down the opposite bank, for a tour of historic wine lodges. Sandeman Cellars (Largo Miguel Bombarda, tel 351 223 740 533, http://www.sandeman.eu) offers daily tours. Or compare different makers at Solar do Vinho (Rua Entre Quintas 220, tel 351 226 094 749, http://www.ivdp.pt).

Porto frees travelers of “gotta-see-it” guilt, allowing — almost begging — a leisurely dawdle in a riverside café to watch colorful wooden boats ply the river. Hop aboard for a better view of the layers of houses clinging to the vertical Ribeira quarter. Cruise upstream to the Eiffel bridge or downstream past wine lodges and toward the Atlantic beaches.

Once you’re back on terra firma, put on your walking shoes. You may wonder if hiking boots would be a better choice as you climb from the Ribeira up the stairs that zigzag switchback-style to the cathedral, but the long river views make it worth the effort.

The Rococo interior of the São Francisco Church is covered in gold — 200-plus pounds of it. Just behind, Palácio da Bolsa is not your usual stock exchange; with a glass-domed atrium in pink neo-Moorish style, its Arab Room is so gilded and embellished with colored tiles it looks more like Scheherazade’s harem.

Browse in nearby Palácio das Artes and Lobo Taste (Largo S. Domingo 20) to shop for work by cutting-edge contemporary artisans before getting lost in Porto’s maze of narrow streets (any downhill route leads back to the river). Discover its quirky secrets — a railway station lined with tile murals, eccentric shops, elegant cafés (even the local McDonald’s has an Art Nouveau interior) and tile-covered churches.

Join the evening flow downhill to Porto’s riverbank. Cafés overflow, restaurants fill, strolling groups of black-caped university students sing on the quay, colorful boats glide past.

When it’s time to savor food instead of river views, look one street back for well-prepared typical dishes at Postigo do Carvão (R. Fonte Taurina 24, tel 351 222 004 539). In the Palácio das Artes, find stylish contemporary cuisine based on local ingredients at DOP (tel 351 222 014 313).

To be sure, there are sights to see — but if you miss one, no matter. Unless it’s watching the river over a glass of Port.