The Bikini Bottom Triangle is an island that is seen in the episode "Welcome to the Bikini Bottom Triangle."
The mermaids are the first people to settle here. The island contains many items taken by the mermaids via singing to activate a giant vacuum, which opens a rift in the sky while doing so. When they sing their song backwards, the items are returned to their owner.
- The Bikini Bottom Triangle is possibly a reference to the Bermuda Triangle.