It’s a blazing hot Sunday afternoon on Half Street, Southeast, just outside of Nationals Park. The heat is nothing new for D.C., though. Washington’s summer scorchers were well known to even the capital’s earliest residents—an assemblage of land speculators, slaves, and government workers—but this Sunday feels especially sticky and unbearable. Not even the breeze off the Anacostia River helps. Despite the weather, packs of baseball fans crowd Half and First and N streets, many clad in sweat-stained jerseys and red wool hats stitched with a curly “W.” Vendors mill around makeshift tents and collapsible tables set up along the sidewalks; some stands teem with T-shirts and jerseys, some with bottled water, “ice cold, ice cold,” and some with the traditional peanuts and Cracker Jacks. Unanchored entrepreneurs roam the area, their arms lined with knockoff caps, hawked to the tirelessly repeated tune, “Five dollars, get your five-dollar hat here, five dollars.” Streams of potential buyers file off the humid, underground Navy Yard Metro, up the station’s escalators, and out into the daylight. Scalpers wade through the crowds chirping, “Tickets, tickets, tickets.”