Listen to fictional noise at the Denver Colorado soundwalk

The Denver Colorado Soundwalk is a sound art piece located on the sidewalk of Curtis Street. Jim Greene's "Soundwalk" uses tape recorders that play sounds through six normal looking sidewalk grates. There are 40-100 various sound selections you can hear per hour. The sounds include "rumbling, gurgling water, farm animals" and more.

I love art that takes something ordinary, such as a grate on a sidewalk, and turns it into something whimsical. I wish I had stumbled upon the soundwalk without knowing what it was prior.

I wonder how people in this situation react to hearing farm animal noises coming from underneath the sidewalk without knowing why.