Leave Porto behind and head east along the Douro, where the river cuts through the oldest demarcated wine region in the world. The drive itself is part of the day — the valley opens up in stages, terraces stacked above the water on both banks.

You'll get off the road and onto the trails above Adorigo, walking through the vineyards on the shale-walled paths that have been in use for centuries. The route takes in the classic Adorigo viewpoint, looking down over the river bend and the terraced hillsides that earned the Alto Douro its UNESCO listing. It's an easy-to-moderate walk on undulating ground, taken at a relaxed pace with plenty of stops for photos.

The reward at the end is a picnic at a boutique winery, one of the small, family-run estates that still make their wine the way their grandparents did. You'll tour the winery and the cellar with your host, hear how the grapes come off these slopes and into the barrel, then settle in for a picnic of regional produce: local cheeses, cured meats, olives, bread and preserves, paired with the estate's own table wine and a glass of Port. Choose your spot on the terrace overlooking the vines, or among the rows themselves.

You return to Porto in the late afternoon.