June 1 is National Donut Day. Get ‘em while they're hot (and free).

Photo Illustration by Mariah Tyler (Images via Getty Images)

When it comes to a sweet treat, it's hard to beat a donut. Whether it's classic glazed, custard-filled, or maple topped with bacon, donuts do it all: you'll find them on plenty a breakfast menu, pairing perfectly with a hot, black coffee, but they work just as well as an afternoon snack or an after-dinner delight.

It's true, there's never a bad time for donuts, but if you're looking for an excuse to indulge, National Donut Day is here to help — and offer up free donuts across the U.S. Every year, the holiday falls on the first Friday in June. As the story goes, during World War I, Salvation Army sent a few hundred volunteers to Europe to support troops. One of their jobs was to bake for the soldiers, but that proved tricky on the frontlines of war. The volunteers wound up frying donuts in the soldiers' helmets, earning themselves the nickname "Donut Lassies." In 1938, Salvation Army announced a holiday to commemorate the efforts of those volunteers, and voila! — we got National Donut Day.

Of course, anyone who misses out on the first donut-related day of the year can play catch-up later on Jelly-Filled Doughnut Day, on June 8; Cream-Filled Donut Day, on September 14; and then the other National Donut Day, on November 5.

It's safe to say the donut has worked its way into the fabric of America, but the doughy treats didn't get their start here. The most popular theory is that Dutch settlers brought the original donuts to the U.S. as olykoeks, or "oily cakes."

WATCH: Where to Get Free Donuts and Sweet Deals on National Donut Day 2018

Today's donut has evolved since the days of oily cakes and frying pans fastened out of helmets. While the classics like cake donuts and old fashioneds are still popular, one survey found that over 80 percent of Americans would try wilder versions, like breakfast cereal, mango, or alcohol-inspired flavors. Regardless of what kind we're eating, we're eating plenty. On average, Americans put away 31 donuts each year.

There's no shortage of options, either. Some counts put the number of donut shops in the U.S. at over 25,000. While there's certainly nothing wrong with doing your own homework — especially when that includes taste-testing — Yelp has given you a head start by narrowing down the cream of the donut crop. "We identified businesses in the food category with a large concentration of reviews mentioning 'doughnut' or 'donut,' then ranked those spots using a number of factors including the total volume and ratings of reviews mentioning those words," representatives for Yelp explained.

From a traditional Bismarck at Sweet Coloradough in (you guessed it) Colorado, to the Chocolate Couch Potato (a chocolate-glazed with salted potato chips crumbled on top) at Wake N Bake Donuts in North Carolina, here are the top spots to grab a donut (or a dozen) in every state, according to Yelp.

Alabama: The Donut King, Eufaula

Arizona: Novel Ice Cream, Phoenix

Arkansas: Mark's DO-Nut Shop, North Little Rock

California: BJ Cinnamon, Folsom

Colorado: Sweet Coloradough, Glenwood Springs

Connecticut: Neil's Donuts and Bake Shop, Wallingford

Delaware: Sandy Pony Donuts, Bethany Beach

Florida: Mojo Donuts, Pembroke Pines

Georgia: Scream'n Nuts, Alpharetta

Hawaii: Donut Dynamite, Wailuku

Idaho: Sweet Sensation Donuts, Meridian

Illinois: Country Donuts, Crystal Lake

Indiana: Long's Bakery, Indianapolis

Kansas: Mr D's Donut Shop, Overland Park

Kentucky: Nord's Bakery, Louisville

Louisiana: District Donuts Sliders Brew, New Orleans

Maine: The Holy Donut, Portland

Maryland: 202 Donuts, Bethesda

Massachusetts: Donut Shack, Lowell

Michigan: Avon Donuts Inc, Pontiac

Minnesota: Cardigan Donuts, Minneapolis

Mississippi: Fantasy Donuts, Biloxi

Missouri: Pharoah's Donuts, Saint Louis

Montana: Granny's Gourmet Donuts, Bozeman

Nebraska: Olsen Bake Shop, Omaha

Nevada: Doughboys Donuts, Reno

New Hampshire: White Mountain Cider, Glen

New Jersey: Purple Glaze Donuts, Asbury Park

New Mexico: Rebel Donut, Albuquerque

New York: Stax Ice Cream, New York City

North Carolina: Wake N Bake Donuts, Carolina Beach

North Dakota: Sandy's Donuts, West Fargo

Ohio: Bill's Donut Shop, Centerville

Oklahoma: Sweet Mini's Donut Company, Oklahoma City

Pennsylvania: Beiler's Bakery, Philadelphia

Rhode Island: Knead Doughnuts, Providence

South Carolina: Rainbow Donuts, York

South Dakota: Baker's Bakery & Cafe, Custer

Tennessee: Donut Palace, Murfreesboro

Texas: Round Rock Donuts, Round Rock

Utah: Create Donuts, Sandy

Vermont: Cold Hollow Cider Mill, Waterbury Center

Virginia: Texas Donuts, Centreville

Washington: Daddy's Donuts, Kenmore

Washington, D.C.: District Doughnut and Coffee, Capitol Hill

West Virginia: Peace Love and Donuts, Huntington

Wisconsin: Cranky Al's Bakery and Pizza, Wauwatosa

Wyoming: Delish Donuts & Coffee, Alpine