The Turtle Lair is the home of the Turtles and Splinter. It is located underground in the sewer tunnels of New York City. The Mutanimals periodically relocate to the lair, as they did following the events of the Mutant Mayhem movie. They also sheltered in place in the lair during the storm that began in Raph vs. Water.
The lair primarily consists of one large room with designated areas. There are a short set of stairs used to reach the kitchen space as it is set a little higher than other areas. A Port-O-Potty serves as a toilet closet while nearby is a bathtub with a shower curtain hanging from piping overhead. Donatello has a desk and computer against one wall behind the couch and the television is wall mounted facing the couch. Splinter's favorite chair has a floor lamp next to it and is near the round wooden table in the center of the space. There is a pay phone on one of the support columns.
In another section of their lair is the space which is the shared bedroom of the Turtles. There are semi-private spaces for each of their beds, with Michelangelo's bed being inside a cut-out section of piping reached by a ladder.