Photo of Thomas Circle in 1922 from Flickr user NCinDC 

“I’ve been told that the traffic circles, most with statues, in Washington were purposefully placed two cannon ranges apart so the city would be defensible from any point. Is this true, in whole or part?”—Kay Larson

As far as we can tell from our research, Kay, that wasn’t quite the case—though the traffic circles did have something to do with defending the city. While the circles throughout the District may now seem like a nuisance, they were originally meant to do more than frustrate drivers. Read on for the explanation.

Photo by Flickr user IntangibleArts 

“What the heck are those grass-covered rounded structures at the southeast corner of North Capitol street and Michigan Avenue? They look like something out of an old war movie.” —Sarah

Although they may look like a backdrop for Tom Hanks in Saving Private Ryan, the structures are actually abandoned sand washers that are part of the McMillan Reservoir’s sand-filtration system.

Alejandro Salinas asks: “What is Dupont Underground? Where is the entrance located? What’s the story behind it?”

The National Capital Trolley Museum staff and the Web helped us unravel the mystery of the Underground, while members of the Arts Coalition for Dupont Underground discussed its possible reincarnation with us. Read on for the scintillating answers!

Dupont Underground is an abandoned streetcar/trolley terminal and tunnel, which is located underneath Dupont Circle but above the Metrorail tracks. Several boarded-up entrances can be seen around the circle, including spots near PNC Bank and Krispy Kreme.

Photo by Flickr user dbking

“What’s the deal with the statues on horses? Is there any significance to them? I’ve heard that there’s some significance when their front leg is lifted.” - Liz Palmer

Several readers were wondering the same thing, Liz. With help from a reference librarian and good old-fashioned Internet digging, we’ve got it covered.

"While waiting at the bus stop at the southwest corner of 7th and Constitution, I’ve often wondered what might be the origins of that (sandstone?) monolith. There’s no sign or any other marker to indicate why it is there. Is it perhaps some remnant of the old B&O railroad station?" - Paul Symborski

Glad you asked, Paul! To find the answer, we put our Googling skills to the test.

Photo by Flickr user rachaelvoorhees 

Editor’s note: Washingtoniana was a monthly feature that first appeared in The Washingtonian magazine in the 1980s. It was penned by then-senior editor Lynne Cheney, wife of Vice President Dick Cheney. Subsequently written by other editors, the feature appeared on-and-off in the magazine through the mid-1990s.

In our search for Adams Morgan’s history, we tracked down Josh Gibson, the guy who literally wrote a book on the subject; the Adams Morgan resident and local historian coauthored Then & Now: Adams Morgan.

In the early 1900s, he says, the lively nightlife neighborhood we now know as Adams Morgan was known more by its geography than anything else; people simply referred to it as its cross-streets, 18th and Columbia. As a whole, it comprised parts of four other neighborhoods, including Lanier Heights to the northeast and Kalorama to the west.