Fort Nuestra Señora de la Soledad sits on a low promontory overlooking Umatac Bay, offering the best view in the village from its crumbling parapet. The Spanish built it in the late 18th century to defend the bay — one of the natural harbours on the western coast of Guam — against the British and other European rivals. The walls are substantial and mostly intact, though the interior has long since returned to scrub.
The fort is not a formal museum and can be entered freely. Spend fifteen minutes walking the walls, then another fifteen looking out over the bay, which from this angle shows the green hills, the channel, and the open Pacific in a way that makes it obvious why Magellan chose to land here. There are information boards with a brief history in English.