Herculina

Herculina, formally designated 532 Herculina, is a large asteroid roughly 225 kilometers across. It began as a mining operation and stayed in zero gravity through that working life, until it was spun up later at considerable expense. The station inside has since been repurposed and largely rebuilt: interiors carved out of stone and finished with molded plastic, corridors and rooms kept spartan with no attention paid to decor.