Some extra tips to help you find your way...
Connected to Angell Hall, the huge building with the large columns on State Street that is located next to Museum of Art. To enter Mason Hall, enter from the side of the building that faces the Diag, not the side facing State Street. The door on the far-left is unlocked even though all the other doors will be locked. After entering, go down the hallway to your right, past the "Fishbowl" (computing center) and take the elevator up to the desired floor.
Connected to Mason Hall. You will have to enter building from the Diag side (same entrance as for Mason Hall).
Michigan Union (530 S. State St.)
The Anderson Room, Wolverine Room, and U-Club are on the first floor. The Union Ballroom, Parker Room, and Pendleton Room are on the second floor.
Michigan League (911 N University Ave.)
The Vandenberg Room and League Ballroom are on the second floor.