Y2

YOU ARE IN A LARGE ROOM, WITH A PASSAGE TO THE SOUTH, A PASSAGE TO THE WEST, AND A WALL OF BROKEN ROCK TO THE EAST. THERE IS A LARGE "Y2" ON A ROCK IN THE ROOM'S CENTER.

From here:

You can use magic to go back to the building, PLUGH. Or you can go south to a low n/s passage. Or you can go east to a jumble of rocks. Or west to a pit.. Or use a magic word again, PLOVER..