And here’s what’s currently in the NISMFs: https://en.wikipedia.org/wiki/Naval_Inactive_Ship_Maintenance_Facility
I grew up in Long Beach, Cal after the war—the big one. There were lots of ships in mothball there at the time. Of course someone had to patiently explain to be that there really weren’t a lot of mothballs in the ships.
I can also remember Long Beach harbor filled with Navy ships when “the fleet was in”. Impressive sight.