This structure has survived the previous 30-100 thousand years. The curved portion used to be a high-tech glass/plastic half-dome, but it has since broken, and the pieces are strewn across the floor. At least, those pieces that haven't been carted off for nefarious purposes or construction. A stairway leads down to the tubecar. The roof of the back rooms is missing, and the two walls of the larger room are crumbled.
These were drawn with a 0.4 mm black india ink Faber Castell Pitt artist pen on an acid-free sketch book. The images were touched up digitally, and the side view was combined from two drawings.