Tokyo is a city built on rivers and streams, and much of its history is built around waterways, yet it took until last weekend to finally enjoy a really decent yakatabune boat ride. I’ve been here for decades and been on cruises and even ridden in yakatabune, which are long, flat boats with tatami mat rooms used mostly for sightseeing cruises, but I hadn’t really cruised on one. I’d always associated them with geisha asobi, parties with geisha, and raucous, bawdy boat trips (and a look at the cruise options available will show that I’m not wrong), but that’s not…