If you weren’t already mad at D.C. tour guides for clogging sidewalks with eighth graders in matching shirts, you can curse them for spreading lies.

“We like telling good stories, even if they aren’t quite true,” says local tour guide Robert Pohl. “I almost certainly propagated some before I started being more careful about researching what I talk about,” he says.

In “Urban Legends & Historic Lore of Washington, D.C.,” Pohl sought the truth. Here are some of his favorite debunked myths, which he’ll also discuss at Politics and Prose on Sunday.

D.C. Was Built on a Swamp

The image of the nation’s capital being constructed atop a fetid cesspool may ring true, but it’s factually incorrect. “There was a swampy area called Swampoodle near Union Station, but less than one percent of D.C. was swampland when the federal government moved here in 1800,” Pohl says.

Georgetowners Refused a Metro Station

Popular lore has it that short-sighted Georgetown residents objected to a Metro stop for fear that easier access to the neighborhood would lure riffraff, but no station was ever planned, Pohl found: “Metro was really designed to be a commuter rail, to bring people from the suburbs into the [center of the] city.”

The Origin of the Word ‘Lobbyist’

Sorry, Willard Hotel. Though political advocates may have loitered in the your lobby hoping to chat with President Ulysses S. Grant, the political use of the word “lobby” dates back to 1640, when regular British folks talked with their representatives in the lobbies of the House of Commons, according to the Oxford English Dictionary.

The Existence of a ‘Hoof Code’

In D.C., an equestrian statue’s stance does not provide clues as to how its rider died, Pohl says. In Gettysburg National Military Park, however, most of the horse statues do follow a pattern whereby people who died in battle ride horses with two hooves on the ground, while those who were merely injured sit on animals with three feet planted on terra firma. “It seems to be a coincidence, though,” Pohl says.

Why There’s No J Street

Many tour guides claim that the District’s planner, Pierre L’Enfant, left out J Street because he was feuding with Supreme Court justice John Jay. It’s more likely, however, that the street was skipped because I and J were considered interchangeable at the time, Pohl says: “Dictionaries from the late 1700s didn’t even have different sections for I and J.”

Taft Got Stuck in a Bathtub

President William Howard Taft never got stuck in a White House bathtub, but he did have an extra-large one installed to prevent just that. The 6-foot-tall president weighed in at 355 pounds, and “generally preferred to shower,” Pohl says.

Politics and Prose, 5015 Connecticut Ave. NW; Sun. 1 p.m., free; 202-364-1919. (Van Ness)