Sure, you know the place down the block from you, and maybe the one a couple of streets over. And the one by your friend’s house where you sometimes stop by to pick up a six-pack on your way to visit. But how many corner stores are there in the District, all told?

Defining them is more art than science, but here’s a stab at systematically identifying all of D.C.’s businesses that fit the bill. Each of these establishments has an active retail license to sell alcohol, cigarettes, groceries, and/or food products, in a building and property of less than 10,000 square feet, located within 150 feet of a zone that allows residential development. Chain grocery stores and pharmacies don’t count, nor do gas stations.

That adds up to more than 500 stores. Quite a few of their names give deference to “The Corner” (Charlie’s Corner, Cookie’s Corner, Cornercopia) or to the intersecting streets that form the corner (18th & D Liquors) or both (11-M Corner Market). Many are joint ventures: P&C, B&M, K&H (and just about every other possible permutation), Stop & Go, Me & My, Night N Day.

This map shows where these corner stores are located and identifies some of the neighborhoods blessed with the highest concentrations of such establishments. The densest stretch? A strip near Kennedy Street and Georgia Avenue NW, with one store for every 170 residents of the surrounding blocks.