People build swing sets, tree houses and even skating rinks for their kids, but a Minnesota man has created an indoor fun house just for cats.
Greg Krueger has spent the last 15 years, carefully carving through walls, creating elaborate walkways and passages in his home.
PHOTOS: Minnesota man builds a dreamhouse for his cats
The all for his four cats, who enjoy exploring nearly 100 yards of elevated catwalks.
Krueger has a form of autism called Asperger Syndrome.
He says he has trouble interacting with other people, but his cats are a different story.