The Great Big BOO at Gilroy Gardens, September 27 - October 27, 2024. Trick or Treat: Get dressed up in costumes and take the kids around the BOO Trail to trick-or-treat for candy. Boo Alley: Visit Boo Alley and discover "Boo-tiful" light displays throughout the park and enjoy the ultimate interactive Halloween experience as you … Continue reading "Halloween | Gilroy Gardens"