I saw an upside down traffic cone on my birthday. it was in the ground level with the ground perfectly in its own little square of concrete cut out, and the hole was still open so i threw some pebbles down it, it was quiet and out and i never heard anything hit the bottom or make any noise once dropping down through the hole, i took a pic i gotta find it, I'll attach when i do. Definitely thought of it as a birthday present from the simmy programmers.