Two Falmouth residents are planning to open a distillery in June in Portland’s East Bayside.

Dave McConnell, a Portland attorney who has advised many craft beer makers in his 23-year career, is teaming up with his friend Sam Pierce, founder of the Portland-based software service IW Financial, to open a rum distillery called Three of Strong. The name comes from a Colonial-era punch recipe: “One of sour, two of sweet, three of strong and four of weak.”

“After 23 years, I thought would be really fun to connect with something I’m really passionate about,” McConnell said.

Three of Strong has leased 6,200 square feet in the Rockingham Electric building at 35B Diamond Street. McConnell said they have hired Graham Hamblett, master distiller at Dogfish Head Distilling Co. in Delaware. Crystal Pomerleau, who has worked at several well-regarded Portland restaurants, will be manager of the tasting room.

McConnell said the distillery will begin with making rum, both because he and Pierce “really love rum” and because of Portland’s strong historical connection to the drink. Pierce’s family also has connection, McConnell said; Pierce’s ancestors distilled rum in the 1750s on the Charles River in Watertown, Massachusetts.

As Three of Strong begins distilling its own rum, the company will also source aged rum from a family distillery in Barranquilla, Colombia, on the Caribbean coast. The Portland distillery will sell the South American distillery’s 12-year-old rum, and use its 5-year-old rum for blending, McConnnell said.

Three of Strong also plans to make a spiced rum. Chef Evan Mallett, owner of The Black Trumpet restaurant in Portsmouth, has developed a spice blend for the Portland rum, McConnell said.