Deep under the moon's sea lay countless domed cities and factories, built after the lunar bombardment that destroyed their land. Millions live inside these great domes, making comfortable lives for themselves behind the crystal walls. Where gardens flourish and fields of red grain stand taller than a locomotive, where submarines deliver goods to and fro.

Shown in the picture is the fringe of Toriummora where the moonpools and red grass grow. The moonpools are what allow the free movement of submarines in and out of the dome.

More worldbuilding. Hope you enjoy!