Leandro Erlich's "Swimming Pool"

This is the link to an installation by Leandro Erlich. I came across it while going through Instagram and was really intrigued because I didn't know how it worked--I was sure that there couldn't actually be people walking in what seemed to be a swimming pool. I was partially right. The "pool" is just 10 cm of water that is supported by a thick layer of transparent glass. Underneath the pool is a room that people can enter and walk around in, effectively making them a part of the installation. I really like this piece because I think it's an extremely creative way of making people engage with artwork--it's really cool that a viewer can experience the work in such varied ways (from above or below). 

Here are some more pictures (and different views) of the installation:

images from: https://www.ignant.com/2016/01/07/an-illusory-swimming-pool-by-leandro-erlich/