what are river locks and how do they work

It's all about those lock systems. Basically, when you're moving from a lower water level to a higher one, you pull the ship into a concrete chamber, close the big gates behind you, and then they start pumping water in until you're level with the upper part of the river. It’s pretty wild the first time you do it, just sitting there in this giant tub while the water rises around the hull. Once you're level, the front gates open and you just cruise out.

Going the other way is just the reverse, obviously. You enter the chamber, the gates shut, and they drain the water out until you drop down to the lower level. It takes a bit of patience, especially when there's traffic waiting, but these systems are incredibly efficient. I've spent plenty of nights waiting my turn in a queue for a lock, and honestly, it’s just part of the routine when you're navigating certain stretches of water.