http://burgerdays.com

Free burgers are one thing. Free Shake Shack burgers, however, are a whole different story. Today is the day, burger lovers – it's FREE SHAKE SHACK DAY. We're sure you've heard the news: celebrating the opening of its 100th location across the globe, Shake Shack is hooking up free ShackBurgers for the first 100 guests at all its brick-and-mortar locations (sorry Nats Park). Doors open at 10:30 a.m. and we have no doubt the lines will be forming quick. The best bet to snag a free burger is probably Shake Shack's mall locations – Tysons and Pentagon City – though, with the nearby business parks, we can't guarantee those suit-and-tie types won't be ducking out for an extra early lunch today. If you're in the area, the Union Station Shack also might be a little less crowded. Just a reminder, there are six D.C. and Baltimore locations of Shake Shack: Dupont, F Street, Union Station, Pentagon City, Tysons and up at the Inner Harbor in Baltimore. Which one will you pick?