Nihlathak's Temple (Diablo II)
Nihlathak's Temple is the entrance above ground which leads down to the rest of Nihlathak's dungeon. The first time the palyer visits it it is reached by a red portal opened by Anya. This portal will remain open indefinitely until the player activates the waypoint in the Halls of Pain, at which point the portal will close forever.
This has been used to many a player's advantage. The Super Unique located here, Pindleskin, has a monster level of 85, meaning he can drop all items in the game. Since he is easily accessible through the portal, players have often opted never to activate the waypoint here, instead keeping the portal in Harrogath open to allow for very quick and easy runs of Pindleskin, so called 'Pindle runs'.
The three levels below the temple entrance are the Halls of Anguish, the Halls of Pain and the Halls of Vaught. Interestingly, the epithets of the first two levels correspond to those of two lesser evils: Andariel, the Maiden of Anguish, and Duriel, the Prince of Pain.