Photo shows four* Starship Boosters at various stages of assembly inside one of two Mega Bays at the SpaceX Build Site. The two Mega Bays – one for ships, one for boosters – are adjacent to the Starship Factory in Boca Chica, Texas.

A “Super Heavy” booster has very little internal structure. It’s mostly just a liquid oxygen tank stacked atop a liquid methane tank. At the bottom of the methane tank are the 33 engines, and at the top of the oxygen tank are the “grid fins” and the motors that operate them. A pipe runs down from the bottom center of the upper tank through the middle of the lower tank to carry oxygen to the engines. All of the other piping and electronics (and the self-destruct explosives) are attached to the outside.

* The items on the far left and far right will be parts of the same booster.