(Photo by Ricky Carioti/The Washington Post)

Q. Outside Metro Center’s 12th Street Northwest and F Street Northwest entrance, a sign says a big glass canopy is being built to protect the escalators. That makes sense, but why aren’t canopies being built to protect the escalators and the riders from the harsh elements at other stations, like at Archives or Smithsonian?

Both stations are on federal National Park Service property, and the agency is concerned that canopies at those locations — as well as at Arlington Cemetery, U Street/African-American Civil War Memorial and Judiciary Square — “would adversely impact the cultural landscapes and viewsheds of the memorials and park areas in their vicinity,” National Park Service spokesman Mike Litterst said.

But he emphasized, “We have never said ‘no’ to the idea of acceptable canopies in these sensitive locations.”

WMATA, the park service and other organizations have discussed coming up with an acceptable design for the canopies for years, he said.

While Litterst admits it’s been a couple of years since the topic has come up, he suggested the issue could be discussed again soon.

Got a question or story to share? Contact DC Rider at kery.murakami@washpost.com or @theDCrider.

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