At that time there was not the sign of a habitation there or thereabouts, except the fort, and an old adobe-house, east of the fort, known as the hospital.

The fort itself was one of adobe-walls, about twenty feet high, rectangular in form, with two-story block houses at diagonal corners.

The entrance was by a large gate, open by day and closed at night, with two iron ship's guns near at hand.
Inside there was a large house, with a good shingle-roof, used as a storehouse, and all round the walls were ranged rooms, the fort wall being the outer wall of the house.

The inner wall also was of adobe.

These rooms were used by Captain Sutter himself and by his people.