3,857. The Winding Staircase

Hilchos Beis HaBechirah 4:11

Each cubicle had three entrances: to the cubicle on its right, to the cubicle on its left, and to the cubicle above it. The cubicle in the northeast corner on the second level had five entrances: to the cubicle on its right, to the cubicle above it, to the winding staircase, to the cubicle with the small gate, and to the Heichal.

Hilchos Beis HaBechirah 4:12

The winding staircase was used to ascend to the roofs of the cubicles. It went up from the northeast corner of the Temple towards the northwest corner. One climbed the staircase facing west and traveled along the whole north side. When he reached the west, he turned to face the south. He traveled the whole west side until he reached the south, at which point he turned to face the east. He then traveled east until he reached the entrance to the loft, which was on the south.