Sweden’s most famous rune stone, the 9th-century Rökstenen, is near the church at Rök (just off the E4 on the road to Heda and Alvastra, 25km from Vadstena). It’s a monumental memorial stone raised to commemorate a dead son and features the longest runic inscription in the world. It’s an ancient, intricate verse so cryptic that scholars constantly scrap over its interpretation. The outdoor exhibition and stone are always open.

Buses are virtually nonexistent, though the scenic flatlands around Vättern make for perfect cycling.