TWO 20-something sisters sat in Malagana Café & Bar (Calle Tripita y Media 31-55; 57-5660-1360) in the Getsemaní district of Cartagena, Colombia, scanning playlists on their iPad. They weren’t just passing time: the women multitask as D.J.’s, open mic night hosts, waitresses and accountants for this small restaurant and rooftop lounge, which they opened with their family late last year.

“Five years ago, we couldn’t sit here like this,” said one of the women, Diana Herrera Ordosgoitia. “It was just too dangerous. Most of the houses were in very bad shape; there were a lot of drugs and prostitution. Now this is becoming part of the past.”

As Cartagena’s old walled city is filling up with emerald shops and chain stores aimed at cruise-ship passengers, the once seedy neighborhood of Getsemaní has come into its own. A flurry of drinking dens, salsa clubs, tapas bars and boutique hotels like Casa Canabal and Casa Lola are being carved out of the faded 18th-century buildings in this district, which extends from the city walls to the San Felipe de Barajas Fort.

Ms. Ordosgoitia’s small restaurant and rooftop lounge is just part of the influx. In September, the sculptor Emilio Hernández opened Casa Pájaro y Emilio Hernández, a combination art gallery, cafe, ice cream shop and wine bar (Calle de la Media Luna 10-113; 575-660-6801; casapajaroartegelatoycafe.blogspot.com). Its specialty is cholados (6,000 pesos, about $3.40 at 1,770 pesos to the dollar), a traditional shaved-ice snack from the Cauca Valley that uses condensed milk and a rainbow of exotic fruit syrup.