That’s right, scientists have discovered an underwater Octopus City called Octlantis.

It’s home to 15 cephalopods (like octopus and squid) who built their city out of piles of sand, seashells, and animal bones. It’s located in Jervis Bay, Australia, measures just 59′ x 13′, and is close to another octopus city called… you guessed it: Octopolis.

Marine biologists dove down to place four GoPro cameras for a day, recording footage showing social interactions of the Octlantian residents hanging out, communicating, living together, and sometimes beating up foreign octopuses.

‘Some of the octopuses were seen evicting other animals from their dens. There were some apparent threat displays where an animal would stretch itself out lengthwise in an ‘upright’ posture and its mantle would darken’, said Ms. Chancellor.

“These behaviors are the product of natural selection, and may be remarkably similar to vertebrate complex social behavior,” lead researcher David Scheel, from Alaska Pacific University, told Ephrat Livni at Quartz.

So octopuses, and perhaps other sea creatures are smarter than we give them credit for. Instead of wandering the ocean alone and mating, they seem to form communities and settle down around safe rock formations. So far, we only know of these two octopus cities but explorers may discover more such sea creature cities in the future.