Offshore Rooftop 1000 E Grand Ave, Chicago, IL 60611, USA Celebrate Halloween at Offshore Rooftop with live DJs and sweeping Lake Michigan views. Costumes encouraged. Halloween at Offshore Rooftop Celebrate Halloween at Chicago's largest rooftop with a night of music, costumes, and unforgettable skyline views. Join us Friday, October 30, for an elevated Halloween party featuring live DJs, high-energy dance music, curated cocktails, and one of the city's best crowds. Overlooking Lake Michigan and the Chicago skyline, Offshore Rooftop transforms into the ultimate Halloween party. This event features a live musical arts performance by a house/EDM DJ. 21+. ALL SALES FINAL. NO REFUNDS.