The best replacement for fest is halloween haunt.

The best alternatives to fest are rated as following:
★★★★★  halloween haunt
★★★★  hamcrest
★★★★  shark week
★★★★  assertj
★★★★  uispec4j
★★★  horror nights
★★★  knotts scary farm
★★★  mardi gras
★  feast
★  warped tour
★  ozzfest
  beer league
  country fest

Your alternative for fest is not listed? Suggest!
Speaking about fest, one probably shouldn't forget about perry stone.

Other search terms related to fest and their ratings are:
★★★★★ perry stone
You have in mind a companion for fest and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of fest in all years. Click on graph for more.
fest
halloween haunt
hamcrest