A two-day plan: the Old Town and the Rhine on foot, then one outing chosen by what you love.
Summer on the Rhine
Two days is a good length for Basel. The first day is for the Old Town and the river, all on foot. The second is for one outing chosen by interest, with time left to wander.
MorningStart with coffee on Spalenberg, then walk down through the lanes to Marktplatz. Step into the Rathaus courtyard to see the painted arcades.
Late morningCross the Mittlere Brücke for the view along the river, come back and climb the Rheinsprung lane to Münsterplatz.
MiddayThe Münster and the Pfalz terrace above the Rhine. Climb the tower if it is open. Lunch in the Old Town.
AfternoonOne museum in the centre: the Kunstmuseum for painting, or the paper mill in St. Alban for something hands-on. Or walk up to Spalentor instead.
EveningIn summer, a drink on the Kleinbasel riverbank. In winter, a glass of wine at the top of Spalenberg. Dinner in the Old Town.
Yes, for the essentials. One day covers the Old Town and the Rhine on foot; a second day lets you add an outing such as the Fondation Beyeler or the Vitra Design Museum.
Museum Tinguely, the paper mill, the Kunstmuseum Basel or a bouldering session at Elys Boulderloft. Museum Tinguely is free on Thursday evenings and the Kunstmuseum at set times.
Museum Tinguely (free for children under 16), making paper at the Basler Papiermühle, a ferry crossing over the Rhine and Basel Zoo, which has a BaselCard discount.