I'm a big fan of the Alexander horned sphere, which is even weirder. The interior is simply connected (like the interior of a sphere) but the exterior isn't. h

I'm a big fan of the Alexander horned sphere, which is even weirder. The interior is simply connected (like the interior of a sphere) but the exterior isn't. https://en.wikipedia.org/wiki/Alexander_horned_sphere https://en.wikipedia.org/wiki/Alexander_horned_sphere