Fear at Avon Valley Fear, Avon Valley Bristol is top of our list for scare parks in the southwest. There are four terrifying attractions, three that have won awards and a brand new event that's scaring for the first time: The House of Clowns. If you watched It from behind the sofa with the lights on, sit that one out. It runs on select nights from Oct. 19 to Oct. 31, 2018.