No visitors allowed is a lot assignment in The Sims 3, available since launch, and serves as one of the two[note 1] catch-all assignments in the Sims 3 era along with Visitors allowed. Maxis developers most commonly gave this lot assignment to:
As the name indicates, the Maxis dev team did not intend for townies or most other NPCs to visit such lots (and certainly not to enter any doors on such lots) unless they were visiting rabbit holes; but as a result of various oversights in the game's coding, NPCs will sometimes try to visit such lots anyway.
Due to the very large amount of "No visitors allowed" lots across the many The Sims 3 worlds, especially in later expansion packs and Store sets, the list below should not be taken as a definitive guide.
The two versions of The Rose Campground both have one tent, gendered roofed toilets and sinks, a campfire, and many trees, though they're not 1:1 clones of each other.
Camps Peony, Orchid, and Lotus are No Visitors Allowed lots in Shang Simla. They feature tents and toilets so that Sims can rest during adventures. They all look much the same.
Han's Orchard is a pretty No Visitors Allowed lot in Shang Simla. It is a great park for gathering rare fruit like pomelos, and rare types of fish. It's clearly related to the hidden tomb called Han's Barn.
Though similar in the spirit to the dozens of "Rabbit hole and little else" No visitors allowed lots in the Sims 3 era, this particular lot has slightly more facilities than most others of them. The lot can be converted by players into a park (fairly easily), a gym (which takes slightly more effort), or perhaps even a live show venue with 1 or 2 Big Show Crowd floors (Hard to do, but possible).
A fairly large backyard where players can place objects.
It is not known why the lot has the No visitors allowed lot assignment by default, when it was visibly designed to be a library and would thus have been given the Library lot assignment.
Close proximity to a lake that can be swum in if Patch 42 or later is installed.
It is not known why the lot has the No visitors allowed lot assignment by default, when it bears more resemblance to a public pool. Instead, Swim and Soak Station is the sole designated pool lot assignment in Aurora Skies.
A small 14x8sq tarmac sports field. The field is empty by default; depending on the installed expansion packs, it can host basketball, one soccer goal, table tennis, bowling, or simply gym equipment, among other things.
Its school rabbit hole is the smallest in the game (excluding the Lunar Lakes rabbit hole), but has many outdoor facilities and fake classrooms to fill the rest of the lot. NPCs will however usually not use any of those facilities unless the lot assignment is changed to Big park or similar.
It is not known why the lot has the No visitors allowed lot assignment by default, since it strongly resembles hangout lots, and has enough seating to fit almost the entire population of the town.