The size of the ships Nautilus moved

There were about a dozen ships. Like Barry had said, the core was a trio of large ones. St. George tried to work up from the smaller boats on the edge to estimate size, and decided the tanker and cargo ship were each somewhere around twelve hundred feet long. The ship between them was a few hundred feet shorter, but loomed over the others.
The center one was a multidecked cruise ship, the kind Carnival or Disney sailed. There’d been a logo on one of the cruise ship’s big smokestacks, some kind of fish, but it had weathered away and left a blue blur. A thick carpet of dark green covered the top decks.
A cargo ship rested against the cruise ship on the side facing them. Two long staircases reached down from the cruise ship. Stacks of steel containers spotted its deck, and a dense garden covered the rest, just as Barry had said. At least two dozen people worked the plants and soil…
They swung to the right and circled around. There was a large yacht alongside the front of the cargo ship, and an industrial-looking fishing boat with a pair of cranes crossed in front of both of them. Boarding planks and ropes stretched between the ships, and across to a larger but less elegant yacht alongside the fishing boat that extended across the cruise ship’s bow…
Small ships ran along the side of the tanker. A yacht-sized boat. The tugboat Barry had mentioned. Another fishing boat. They were connected by planks and walkways at odd angles.

Excerpt From Ex-Isle, pg 177-179
Peter Clines
https://books.apple.com/us/book/ex-isle/id989619017