Large, manufactured habitats are built using titanium, aluminum, and steel mined on nearby moons and launched into space by mass driver, or are processed from asteroids. Gravity is simulated by rotation, power comes from large solar collectors or fusion reactors, and a thick shell of slag left over from mining and ore-processing operations provides radiation shielding.

O'Neill Cylinders: These are the largest and most expensive space habitats. They are giant cylinders (or sets of coupled, paired cylinders) a few miles wide and several miles long, rotating to provide Earth-normal gravity. Inside is a complete terraformed environment with park and urban landscapes. An O'Neill cylinder can house a few million people, though current populations tend to be lower. Only a few O'Neill cylinders have been built, such as Islandia in L4.

Stanford Torus: These are smaller than the O'Neill cylinder, but still very large. A typical torus is shaped like a bicycle wheel, with gravity and landscaping on the floor of the outer rim and the spokes serving as elevators that lead to a central microgravity hub. It houses about 50,000 people. Again, radiation shielding is a major expense. A few exist in Earth orbit, L4, and L5.

Bernal Sphere: This is a sphere with smaller attached cylinders. The central sphere may be up to a mile in diameter and rotates; the cylinders do not. The sphere is simple to build, but it only has effective gravity in a strip around its equator, which can be inconvenient. Several spheres have been built, each housing a few thousand people.

Smaller Space Stations: These range from the classic wheel-shaped space station that spins for gravity and incorporates heavy radiation shielding to a much more basic 'work shack', 'bubble', or 'beer can' that lacks much of either. These are usually cylinders or spheres 30' to 300' in diameter and (if cylinders) up to five times as long, often made out of old fuel tanks. The only radiation shielding may be a cramped 'storm cellar' for riding out solar flares; the crews either rely on anti-radiation nano or regular rotation.

Asteroid Habitats: See Cole Habitat and Beehive Habitat. Some asteroid habitats exist in the Main Belt or Trojans, but others were constructed from asteroids moved into Lagrange points or planetary orbits. Several dozen exist.