Eat and Drink Free White Castle sliders for National Hamburger Day The original slider from White Castle is topped with onions and one pickle and served between two steamed buns. Photo Credit: White Castle By GEORGIA KRAL May 27, 2014 2:05 PM Print Share fbShare Tweet Email White Castle is celebrating National Hamburger Day on Wednesday with - what else? - free sliders. White Castle's food truck, The Crave Mobile, will be parked in Herald Square from 11 a.m. - 2 p.m., and each person will get two original sliders. If you're willing to wait in line, eating for free in NYC is easy. And even if you don't want to wait, there are freebies to be found. You just need to know where to look. And if White Castle doesn't appeal to you, you can still celebrate National Hamburger Day. Here are 68 other delicious burgers to chose from. By GEORGIA KRAL Share on Facebook Share on Twitter Comments We're revamping our Comments section. Learn more and share your input.