Oh, the Roaring 20s—flappers, jazz, and... Prohibition. Backed by prominent religious groups, the U.S. government outlawed the production and sale of alcohol from 1920 to 1933, which meant if you fancied a drink in the 1920s, you were going to have to go underground.

Illicit watering holes sprouted up in cities across America, and patrons often had to know a secret password or entrance to gain admittance. Inside, these smoky bars served bootlegged cocktails and people from all classes mingled.

Speakeasies became a staple of American culture in the 20s, and though Prohibition is long repealed, Americans still seek out the charm of a backroom bar. New York City is home to countless stunning bars, and has no shortage of classy speakeasies, either.

RELATED: 10 Incredible Airbnbs in New York City to Add to Your List of Accommodations

10 Lower East Side Toy Company (The Back Room)

Tucked away among all the glitz and glamour of Manhattan, you’ll find The Back Room, under the inconspicuous guise of “Lower East Side Toy Company,” though the lounge inside is hardly a place for children.

The bar was once an operating speakeasy, few of which remain, where patrons were served libations in teacups and drink labels were covered with paper bags. The Back Room still operates in the same way, but without the threat of prosecution hanging over your head.

9 Employees Only

Combining the traditional speakeasy atmosphere with a modern cocktail list, Employees Only is a hidden gem in the quirky West Village. Opened in 2004, this 20s-inspired bar is renowned for its retro cocktails, but it also offers a unique menu of American fare.

Employees Only is a favorite hangout of stylish locals and visitors alike. It’s a great bar for those who want elegance in their drinks and atmosphere--not to mention it's open until 4 a.m. all week long. It gets extremely busy during peak hours, so be sure to make a reservation to avoid disappointment.

8 Dear Irving

The perfect Prohibition Parlour might just be at Dear Irving, an upscale lounge with a vintage vibe, but none of the illegal business of the Golden Age. Dear Irving has two locations at Gramercy and on the Hudson, and both are equally swanky.

RELATED: 10 Things You Can Do At The New York State Fair

Dear Irving Gramercy is Prohibition-meets-Paris glamour and almost feels as if you could bump into Hemingway, Fitzgerald, or Joyce. The bar spares no detail in making the most luxurious environment. Dear Irving Hudson is newly opened in the Aliz Hotel with a James Bond theme.

7 PDT

You probably won’t find PDT (Please Don’t Tell) if you don’t know what to look for. Patrons must enter through Crif Dogs, a hot dog joint in the East Village. There, the entrance is hidden in a phone booth where a hostess will greet you, just like you would have had to do for a cheeky drink in Prohibition days.

The narrow bar in the back is made of dark wood and accented with taxidermy. And the best part is if you want a little extra, you can order from Crif Dogs’ menu.

6 Chumley's

Chumley's is the place to go for good drinks and even better history. One of New York’s most famous speakeasies in the 1920s, it became a popular haunt for the literary community even after Prohibition, including the Lost and Beat Generations.

RELATED: 10 Museums So Weird You'll Think We Made Them Up

Today, there is still no sign marking the Bedford Street building, and it retains some of its original character. Its main function is now as a restaurant serving modern American fare, and the interior of the bar has been renovated into a beautiful blend of old and new.

5 Manhattan Cricket Club

The Manhattan Cricket Club, a rare speakeasy on the Upper West Side, is hidden above Burke and Wills Restaurant. It stays true to its cricket theme, decorated with cricket trophies and turn of the century décor.

While the club looks posh, it is open to the public, though members are entitled to special perks. Each member is issued a private locker where they can keep a bottle of spirits of their choosing. However, everyone can enjoy handcrafted cocktails, and the club maintains an inviting, friendly atmosphere.

4 Bootlegger Jack's

With a name like Bootlegger Jack’s, you can expect all the puffy couches and patterned wallpaper a Golden Age parlor to have. Located below Uncle Jack’s Meat House in Astoria, Bootlegger Jack’s has all the life of a 21st-century bar with all the charm of a vintage one.

Bootlegger Jack’s also has a food menu unique to the one upstairs and offers packages if you want to use the venue for a party. Just let your guests know they have to enter the lounge through the unisex bathroom above.

3 Karasu

Perhaps you’ve been to a speakeasy-themed bar before, but did you know there are a number of Japanese-inspired speakeasies in New York City? One absolute must-see is Karasu, modeled after an authentic izakaya, or casual Japanese restaurant and bar.

RELATED: 10 Coolest New York City Rooftop Bars To Visit

Enter through a back door at Walter’s in Fort Greene, and you’ll find yourself transported to Japan. Though there aren’t any gimmicks to get in like other popular speakeasies, the Asian-themed cocktail list and dinner menu will make you forget that you didn’t have to know a secret password for entry.

2 Raines Law Room

Raines Law Room serves snazzy drinks with a side of humor. Playfully named after a 19th-century law intended to repress alcohol consumption in New York, this speakeasy is decorated with a tin ceiling, plush furniture, and velvet-covered VIP area. Due to an increase in business, Raines opened a second location at the William Hotel.

The Chelsea location boasts wall buzzers for the private area, but arrive early because Raines is a popular hangout. And make sure to ring the doorbell for entry—the host’s discretion will decide who enters the dimly lit lounge.

1 Little Branch

Sometimes you just want a relaxed drink without the noise of unruly company, and Little Branch in Greenwich Village is a fabulous place for a quiet night in a comfortable lounge. Bartenders are even dressed in period-appropriate clothing and certain behavioral rules must be observed in true Prohibition form.

The staff all have an extremely well-cultivated knowledge of cocktails, and they might even create you a custom drink. You won't miss the single doorway on the corner of Seventh Avenue and Leroy Street.

NEXT: 10 Best Free Things To Do In Las Vegas