>>18008300A pool area with a fence around it to keep young children from wandering in and drowning. Frankly speaking having a pool area that isn't enclosed in just opening yourself up to ungodly amounts of civil litigation. Pools are considered "attractive nusiances" so if a child wanders into your backyard and drowns then you can't just handwave their death away with trespassing and their parents can sue you.
https://en.wikipedia.org/wiki/Attractive_nuisance_doctrine