The Great Hall (しろダイヤの いきさきは？ lit. White Diamonds' Destination is? in Japanese) is a level of sorts and is also the thirteenth level of the third island in the original Crash Bandicoot. At first glance it is not much of a level, with the exit accessible immediately upon entering the level. Its secret is revealed once the player has obtained every clear gem in the game, however, as they form a pathway to a secluded balcony. By clearing the hall and reaching the balcony, the player will see Tawna sitting on a bird waiting for Crash. Then the two bandicoots will ride the bird and fly out of Cortex Castle. Then the alternate ending begins by showing epilogues for the bosses, depicting what happened to them after the events of the first game. Then the credits roll as we still see Crash and Tawna flying away on the bird.
When the player reaches the end where Tawna is waiting, one will notice that she's wearing her original green skirt, but when they fly away she's back to her blue skirt. This could possibly be a small error that the producers forgot to fix.
The six colored gems are nowhere to be found along the path, despite being required to collect several of the clear gems.
Due to it's nature, The Great Hall is the smallest level in the series, accounting for both it's normal route and the route unlocked after acquiring all the gems.
The Great Hall doesn't exist in the prototype. This is because gems were not developed yet for the player to collect.