Birch beer might get mistaken for root beer, but it does its own thing. Instead of using roots and spices, it's made straight from birch tree bark, usually the black birch or sweet birch variety.

“This is root beer made from spilled root beer that has been cleaned up with a mop,” wrote one Reddit user. “The root beer/mop water then resides in a mop bucket for a week and then canned.

The drive-in may not look like much but its engrained with tradition, making some of the best root beer I’ve ever sipped. Arriving at your car window in a chilled mug, this is is a root beer ...

"Edward C. Barq’s 1898 root beer formula, crafted in an unassuming white house in Biloxi, Mississippi, stood out from the pack because of its use of sarsaparilla instead of sassafras.

"Edward C. Barq’s 1898 root beer formula, crafted in an unassuming white house in Biloxi, Mississippi, stood out from the pack because of its use of sarsaparilla instead of sassafras.

"Edward C. Barq’s 1898 root beer formula, crafted in an unassuming white house in Biloxi, Mississippi, stood out from the pack because of its use of sarsaparilla instead of sassafras.

"Edward C. Barq’s 1898 root beer formula, crafted in an unassuming white house in Biloxi, Mississippi, stood out from the pack because of its use of sarsaparilla instead of sassafras.

"Edward C. Barq’s 1898 root beer formula, crafted in an unassuming white house in Biloxi, Mississippi, stood out from the pack because of its use of sarsaparilla instead of sassafras.