Tier Breche

Tier Breche was a cavern housing the Academy of Menzoberranzan, which consisted of Arach-Tinilith (the clerical school), Sorcere (the wizarding school), and Melee-Magthere (the fighters' school).

Tier Breche, was technically the name of the cavern where the Academy was located, but in common usage "Tier Breche" often referred to the Academy itself.

Structure
Tier Breche was a small side cavern off the main city cavern and consisted of the highest point in the city of Menzoberranzan.Additionally, two large spider statues can be animated to protect the Academy. It housed the three school complexes, which were carved from stalagmites and rock. Melee-Magthere, shaped like a pyramid, was located in the east. Sorcere, a many-spired tower, was located near the western wall. Arach-Tinilith, a spider-shaped complex and the largest of the three schools, both in terms of physical and numerical size, was located at the north of the cavern. A large staircase connected Tier Breche with the main city cavern. Two sentries, generally former students of Melee-Magthere, stood guard at the twin pillars.

There were magical wards around that Tier Breche were designed to keep out unfriendly spirits; when breached, the wards sounded a loud alarm. Additionally, two large spider statues could be animated to protect the Academy.

History
The Academy has been located in Tier Breche since its founding.

In 1372 DR, during the Silence of Lolth, the Academy's wards were broken several times as Arach-Tinilith was attacked by demons, who had secretly been summoned by Gromph Baenre, the Archmage of Menzoberranzan, to slay Quenthel Baenre, the Mistress of Arach-Tinilith. None of these attempts were successful, however.

Generally, students who had entered one of the schools in Tier Breche were not allowed to leave, but after the city's attack on Mithral Hall in 1358 DR, these rules were relaxed somewhat.