Guest bartenders from pubs across Charleston will compete in a friendly battle for best negroni at Warehouse this Sunday.

Gin, vermouth and Campari. The Negroni is deceptively simple. Joy Richard, a bartender at Mash, thinks the Negroni has become a classic because it's complex in flavor and well balanced. "It's plays to a lot of different flavors," she says. "And it's pleasing to the palate."

Negroni Week, a nationwide fundraiser, kicks off today. Last year, they raised $537,439 for charities that are selected by the bar. In Charleston, Negroni Week is not just about the Campari but it's also about the gin called Hat Trick made locally by High Wire Distillery.

This is not your father's Beefeater. Hat Trick Gin is special and not just because it's made here. Gin historian and blogger Aaron Kroll describes it this way: "All in all, a lot of complexity, and a good deal of balance as well. Each note segues into the next elegantly and smoothly. The finish is clean and refreshing, even neat, with barely a touch of heat to overwhelm it. I’m quite impressed and quite a fan."

Nearly 30 area restaurants and bars will participate in Negroni Week, agreeing to donate $1 of each Negroni sold to a charity of their choice, and 20 of those are also participating in the Amazing Hat Trick Negroni Tour, which rewards Negroni fans who collect stamps along the way (you can pick up a passport booklet at the bars and restaurants on the tour). 

Richard has one specific rule for riffs on classic cocktails: don't call it a Negroni if it's not a Negroni. At Mash, they will be serving a drink called Maximum Effort, which is Hat Trick Gin, tea-infused Campari, Otto's Athens vermouth, rhubarb syrup, pineapple syrup and a dash of Fee Brothers black walnut bitters. 

On James Island, Famulari's is making a Tropical Negroni with Plantation Pineapple Rum, Campari, sweet vermouth, pineapple juice and Cava sparkling wine. 

1Kept has a Summer White Negroni that builds on a base of Bombay London Dry Gin with raspberry-vanilla coriander-infused Campari and Dolin Blanc Vermouth. 

The variations and creativity are endless.

Kick off Negroni Week tonight with High Wire and Bottles at the Warehouse on Spring Street tonight, Monday, June 4, 6-9 pm, where you can collect the first stamp on your Negroni Week tour. 

Follow Stephanie Barna on Twitter @stefbarna.