Dark Horse Coffee Roasters operates its production roastery in Grantville at 5980 Fairmount Ave, Suite 100, San Diego, CA 92120, where the company roasts all of the direct-trade beans that supply its six San Diego cafes and one location on Kauai, Hawaii. Brothers Daniel and Bryan Charlson founded Dark Horse in 2013, bringing a Hawaiian-rooted approach to community and coffee culture that has since scaled into one of San Diego's most recognized independent roasting brands. Direct-trade sourcing relationships connect the roastery to smallholder farms in Guatemala, Ethiopia's Yirgacheffe region, and Colombia, where growers like Elkin Guzman produce experimental lots including a hydro-honey processed Orange Bourbon. The same Grantville strip that houses the roastery feeds into Gaglione Bros Famous Steaks & Subs, a cheesesteak institution that draws its own lunch crowd from the surrounding 92120 commercial district. Fairmount Avenue runs north-south through Grantville and intersects with both Mission Gorge Road and El Cajon Boulevard, placing the roastery at the geographic center of the neighborhood's commercial corridor. The roastery location doubles as a full cafe with espresso, French press, pour-over, and cold brew on the drink menu, plus breakfast items and a merch store stocking t-shirts, jackets, mugs, hats, and vinyl records. Mutual Friend Ice Cream, Dark Horse's sister company, operates out of the South Park cafe and supplies affogato pairings that merge house-churned ice cream with freshly pulled espresso shots. The NightWave half-caff blend is roasted specifically for drinkers who want the flavor depth of a full-extraction coffee without the full caffeine load, and it has become one of the roastery's top-selling retail bags. SDSU sits roughly two miles east along El Cajon Boulevard, and the Grantville roastery catches a steady stream of campus-adjacent commuters who prefer a single-origin pour-over to chain-cafe drip. The Mission Gorge Road corridor running north from the roastery funnels weekend traffic toward Mission Trails Regional Park, and the post-hike crowd overlaps with the late-morning coffee rush along Sombrero Mexican Food's breakfast-burrito window nearby. The Haupia Foam Cold Brew — a coconut-cream-topped cold brew inspired by the Charlson brothers' Hawaiian roots — is the signature drink across all Dark Horse locations and is poured exclusively from Grantville-roasted beans.