Accessed through a still life painting found near the kitchens; to reach it, you enter a door to the right of the main staircase in the Entrance Hall and down a staircase there.
Although it is therefore at dungeon level, it is "as dissimilar as possible" from the Potions classroom. As we have seen in the other common rooms, it is decorated in House colors, which in this case means that there are lots of yellow hangings; like Gryffindor Tower, it has a lot of comfortable armchairs. There are "little underground tunnels leading to the dormitories, all of which have perfectly round doors, like barrel tops
