Do not be mistaken by its name "boat rental". While you can rent a small blue boat here, which is actually quite fun in its own way (except maybe when it is too hot in summer or too cold in winter), I recommend this place in particular for going on a private ride on one of those longer wooden boats with a roof, called "Yakatabune", operated by a boatman. I have walked around this area literally over a hundred times and was genuinely surprised how amazing this boat ride felt.
Private boat ride:
A 30-minute private ride on Yakatabune costs 4,000 JPY in total for up to 2 people (extra charge for one more adult - 1,800 JPY, for one more kid - 800 JPY).