Free Shake Shack Burgers On August 16

To celebrate the opening of its 100th location in Boston's rising Seaport District, Shake Shack is giving away free burgers on August 16.

But before you go running to your nearest Shake Shack that day, there are a few things to be aware of. Only the first 100 guests at Shake Shack restaurants worldwide will receive a free single ShackBurger® (or a burger of equal or lesser value). Note that this also excludes stadiums and ballparks. Guests are welcome to stop by between 10:30 a.m. and noon on Tuesday, but we don't think they'll last that long.

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According to Boston magazine, the Seaport location is selling two exclusive flavors of custard, including Strawberry Crunch Cake (vanilla custard with marshmallow sauce, crumbled sugar cone cookies and fresh strawberries) and the Seaport Salt & Malt (chocolate custard, salted caramel sauce, chocolate toffee, Somerville-produced Taza dark chocolate chunks and malt powder). This particular Shake Shack is the first restaurant to open in the Seaport area and the fifth Massachusetts location.