You might consider parking at the Greenbelt Metro station....
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You are tempting me, but how safe is the Light Rail these days?
I haven’t heard of any incidents in quite some time. Ever since a fatal crash @ 4 years ago they have had endless track work. I ride somewhat regularly and feel safe. hahahaha -— LOTS safer than driving on the Beltway.
As to crime AT the stations (punks), haven’t heard of that in quite some time, either.
Greenbelt Metro Station works for visitors from the N; Vienna from the W; and Springfield from the S. You can use “Rider Tools” at wmata.com. Now you HAVE to use a farecard ($1.00). They are available at ALL stations. If you’re eligible for reduced (disabled/senior) fares, there’s a special card available at only a few places (possibly by mail). All that info is available at the Metro website under fares or farecards (not the easiest to navigate but with patience, it’s quite doable). DO come. A day at the National Gallery (and you might throw in the Natl Archives across the street) is a wonderful experience.