Way back in 2010, we replaced a bunch of caged windows with chimp-proof glass. On the greenhouse (what we used to call the outdoor area) side of things, this created deep window sills that the chimpanzees appreciated right away.
Below is a flashback video from when the windows were first installed in 2010. You can see that the chimps were still working on getting the hang of navigating the space using the hanging fire hose.
Today, Burrito and Missy were each in their own cubby. The frames are tall enough for chimpanzees to sit in them:
Missy can even sit upright in the smallest of the windows that looks into the playroom loft:
Missy was using her private cubby time to sift through some nut and seed shells:
While Burrito decided to get REALLY comfortable in his sill: