Cedar Crystal Tower Outdoor Friendly Cat Tree Condo - Custom Cages
My dad made my indoor cats a tower/bridge/treehouse so they could safely enjoy the outdoors : r/mildlyinteresting
30+ DIY Catio Ideas That Are Totally Pawsome - PetHelpful
10 DIY Cat Trees and Cat Furniture | Apartment Therapy
Amazon.com : Petsfit 4-Level Outdoor Cat House with Sun Deck, Cozy Sleeping Quarters, Jumping Platform, and Play Area - Perfect for Cats : Pet Supplies
Pet Lover Builds Sprawling Outdoor Cat Tree House in his Backyard