Uppsala's location halfway between Stockholm and the Baltic coast makes it a useful base for several short trips. Sigtuna, Sweden's oldest town, sits 35 km south on the shore of Lake Mälaren and is the obvious half-day excursion — a single, walkable medieval main street with rune stones, ruined churches, and lakeside cafés. Stockholm itself is less than 40 minutes by train and easily filled as a full day from Uppsala.
