The home planet of the Kreetassans, a people with an exacting code of manners, where Captain Archer must make a ritual apology after his dog offends them in A Night in Sickbay.
Kreetassa is the homeworld of the Kreetassans, whom Enterprise first meets in Vox Sola, when a delegation storms off the ship after seeing humans eat in front of one another.
In A Night in Sickbay, set in 2152, Enterprise visits the planet to obtain a plasma injector. Archer brings his beagle Porthos along, and the dog relieves himself on one of the sacred Alvera trees. The Kreetassans are outraged, and Porthos picks up a dangerous infection on the surface, leaving Archer to spend a restless night at his side in sickbay.
To secure the injector, Archer finally returns to the capital and performs the apology demanded of him, an elaborate ceremony that involves body paint and cutting up a tree trunk with a chainsaw.