On Tuesday, we featured the 142nd challenge to see how well you know the Metro system. Here are the answers. How'd you do?

This week, we got 18 guesses. Five of you got all five. Great work Peter K, AlexC, Kevin M, Patrick B, and ArlFfx!

The theme this week was that all five stations have side platforms. Most Metro stations have center platforms, so this theme narrowed down the possibilities a bit. As commenter Hugh noted, all of the stations are also adjacent to a transfer station. That was unintentional on my part.

Image 1: Smithsonian

The first image shows the view looking up the southern escalator entrance at Smithsonian. The Department of Agriculture building is clearly labeled, and this should have been an easy one to solve for that reason.

Seventeen of you knew this one.

Image 2: West Hyattsville

West Hyattsville is our next image. This view is looking northward from just outside the mezzanine. Just north of the end of the platforms, the path leading north from the station passes under the tracks. Another clue is the angle of the mezzanine to the platforms. The mezzanine is triangular and juts out from the patforms, with the mezzanine walls being about 45 degrees to the platforms. The tall fences on the platform parapet walls are also fairly distinctive.

Thirteen of you got this one right.

Image 3: Eisenhower Avenue

The third picture shows a wide view of Eisenhower Avenue. This station is one of two Gull I stations with side platforms (the other is Cheverly). The design of the station here also brings the Gull I canopy down to cover the bus loop, which is a nice touch of architectural continutity. The power lines in the background are also a clue for solving this one.

Fifteen of you figured this one out.

Image 4: Ballston

The fourth image proved to be more difficult than I'd expected. Many of you correctly noticed the three sequential tuning fork-style escalators. There are three stations where there are three escalators in this arrangement: Ballston, L'Enfant Plaza, and Pentagon City. You should be able to discard L'Enfant easily, because the Green/Yellow platforms at that station are significantly wider, and there's room to walk on either side of the escalator where it lands.

The definitive clue, though, is the temporary terminal supervisor's booth visible here to the left of the farthest escalator. This booth is located on the New Carrollton platform at Ballston, and dates back to the 1979 opening of the station, when it was the end of the Orange Line. Pentagon City was never a terminal station, and doesn't have a supervisor's booth.

Nine of you guessed correctly.

Image 5: Arlington Cemetery

The final image shows the mezzanine at Arlington Cemetery. I worried that this would be a fairly difficult clue, despite the unique arrangement of this mezzanine. But several of you seemed to get it easily.

Arlington Cemetery is fairly unique in that riders need to descend to get to the mezzanine and then ascend back to the platform. At most surface stations, the mezzanine is above the platforms. However, if you look closely at the image, you can note some key details. As Peter K pointed out, the entrance escalators (to the right) are oriented in to be aligned with the passageway to the trains. At other stations where you descend to the mezzanine and then ascend, the entrances are oriented either perpindicularly or require a U-turn. Examples include Brookland and Minnesota Avenue.

Additionally, at far left, you can see the escalator that ascends to the Franconia platform. It's perpindicular to the entrance escalators (out of frame to the right), and it's also a solitary escalator. Very few Metro stations have solitary escalators. They're usually in an array of two or three side-by-side, except for tuning-fork mezzanines like the ones at Ballston, as shown in image 4.

Seven of you came to the correct conclusion.

Great work, everyone. Thanks for playing! We'll be back in June with challenge #143. As a reminder, whichWMATA will be going on break during May.

Information about contest rules, submission guidelines, and a leaderboard is available at http://ggwash.org/whichwmata.

Matt Johnson has lived in the Washington area since 2007. He has a Master’s in Planning from the University of Maryland and a BS in Public Policy from Georgia Tech. He lives in Dupont Circle. He’s a member of the American Institute of Certified Planners, and is an employee of the Montgomery County Department of Transportation. His views are his own and do not represent those of his employer.