This weekend, the Park Avenue Armory plays host to the New York Antiquarian Book Fair—i.e., Mecca, for a certain type of bibliophile.

At the press preview, I’m conspicuously underdressed, having (lazily) assumed bowties and sweater-vests would rule the day in this crowd. Instead, it’s a sea of chic blue suits. Multiple dealers arrive in sequined floor-length cocktail dresses. At the Bruce McKittrick Rare Books Booth, all the purveyors wear flowered headbands.

Visitors skew more eccentric. Leaning against the Armory entrance, I spy a fellow in cowboy hat and bright chartreuse pants. Which is all to tee up my first question: who are these people?

A rare Eve Babitz.The first fair patron I spoke to—in a dapper newsboy cap—was Jeanne Hilary, a self-identified cartographer and the founder of Bicycle Utopia. An independent historian, Hilary makes maps of Gotham’s under-examined corridors. (“All five boroughs,” she confirms, with no small pride.) She tells me she’s visiting the show to seek out sites of interest for her city guides project.

On the trading floor, the world is represented. I spy sellers from Paris, London, Copenhagen, Milan, Stockholm, and Vienna. At the Illinois based Jeff Hirsch Books booth, I receive a short history of the broadside, a bygone book party favor co-proprietor Susie Hirsch refers to as the “‘Would you like fries with that?'” of readings.”