Circuses. They can be fun. You can go and see jugglers, acrobats, clowns, performing animals, and other sorts of wonders. They can also be pretty horrifying. Often, the two overlap, but nowhere near as much as in Heckna, a new 5th Edition campaign setting that's up on Kickstarter now.
From the campaign:
Heckna! is 5e adventure story designed to take characters through levels 1 to 10. This book is both a setting and a campaign guide with plenty of replayability. Game Masters and players alike will delight in this whimsical, dark carnival setting.
This is a book that combines dark fantasy and fun, campy escapades. It’s designed for players ages 14 and up. However, it’s very easy to adjust the tone and the atmosphere for your party. There’s plenty here that will satisfy horror fans, and just as much that will entice fans of humor and whimsy.
The campaign's more than 6x funded with 28 days to go.