El Reno Fried Onion Burger Day is celebrated annually in El Reno, Oklahoma, honoring the city's famous fried onion burger. This unique burger features a beef patty topped with crispy fried onions, creating a delicious blend of flavors and textures. The event typically includes various activities, food vendors, and live entertainment, attracting both locals and visitors. The day highlights the rich culinary history of El Reno, which has been serving these burgers since the 1920s. It serves as a reminder of the town's heritage and its contribution to American burger culture, making it a fun and tasty celebration for everyone involved.