57.7300°N, 18.7400°E.
Othem Trojaborg is a prehistoric or medieval stone-formation labyrinth in Gotland Island, Sweden. The design is a classical 11circuit layout with 11 circuits, 12 walls, approximately 16 metres in diameter, built of stone. Documented age: Late 19th/early 20th century (Late 19th/early 20th century). Current condition: intact. A 12-wall double-angle classical labyrinth near Othem in northern Gotland. Othem Church (13th century) is among the island's finest medieval churches, with elaborate limestone portals and a rare medieval tower. Documentation sources: Gotland Trojaborgs PDF. Listed in the surveyed catalogue as one node in a larger global registry of the same single design. The labyrinth is one of several hundred sites of this type catalogued globally; each preserves the same unicursal walking-pattern with regional variation in scale, material, and date.
The labyrinth tradition spans at least 4,000 years of documented practice across northern Europe, the Mediterranean, the British Isles, North America, and the Indian subcontinent.