When the Fourth Regiment debuted on the menu at DrinkWell in Austin this year, it wasn’t out of the blue for the bar’s program, which is deeply rooted in the cocktail canon and always features a whiskey-based classic. But what bar manager Caer Maiko reveres about the Manhattan variation is its unexpected flavor profile and light touch, despite its spirit-forward construction.

Toward the end of the 19th century, the combination of whiskey, vermouth and bitters was proliferating within cocktail culture. Drinks that followed this construction weren’t all called “Manhattans”—after all, the Manhattan was still in its infancy. Among them was the Fourth Regiment.

Originally published in an 1889 pamphlet called 282 Mixed Drinks from the Private Records of a Bartender of the Olden Days, the Fourth Regiment calls for equal parts rye whiskey and sweet vermouth, dashes of Peychaud’s, orange and celery bitters and a lemon twist garnish. The recipe also appears in notable turn-of-the-century bar manuals like Applegreen’s Bar Book and Jacques Straub’s Drinks.

But the Fourth Regiment didn’t stay put stateside. Somehow, in the decades following its invention, the drink traveled halfway across the world. The globetrotting writer Charles H. Baker Jr. encountered it in Mumbai (then known as Bombay), where a British naval officer he’d befriended mixed one for him. In his 1931 book, The Gentleman’s Companion, Baker describes the Fourth Regiment as “merely a Manhattan Cocktail made in 4 oz size, spiced with 1 dash each of celery, Angostura and orange bitters.”

According to Maiko, it’s the celery that sets the drink apart. “I love how just a couple dashes of celery bitters are able to completely push what is usually a very fruit- and baking spice–forward cocktail into a slightly savory, fresh and green space,” she says. But instead of using standard celery bitters, Maiko reached for a concentrated celery shrub for its acidic edge.

Part of the Fourth Regiment’s allure lies in how the rye interacts with the celery and vermouth. “[Rye] pairs well with caraway and has those greener, grittier herb notes,” according to Maiko. Specifically, DrinkWell calls for a bonded rye that can stand up to the significant amount of vermouth in the recipe. That being said, she asserts that a lighter vermouth is the best option for the Fourth Regiment. To reinforce the cocktail’s savory notes, she chose Martini & Rossi for its hardy herb flavors, pointing specifically to the presence of oregano and thyme.

And while the original spec calls for a lemon twist, and Baker’s recipe cites a lime twist, at DrinkWell, the cocktail gets an orange garnish instead—a subtle nod to the orange bitters from the original spec that are omitted at the bar.

For Maiko, the Fourth Regiment is an easygoing option for guests who want something that reads as stirred and strong but is actually lighter on its feet due to its equal-parts construction, perfect for this transitional time of year. “If I were to have a spirit-forward cocktail, but I’m sitting in a green garden on a warm summer day,” she says, “this is that version of a Manhattan.”