Parking availability depends on the game, day of the week, and how much you're willing to pay. There are a number of Nationals owned parking lots with varying prices. You can find prices and locations on the Nationals website. There are some private lots with prices starting at $15-$20 depending on game and distance. (Some of these have been replaced recently with construction.) There is also metered on-street parking. There is some free on-street parking at some distance from Nats Park but this changes with development in the area. Be aware that driving in the streets around Nats Park can become very congested and frustrating. Bring patience. Were this 20 years ago, I might also suggest Metro but these days it's more problematic. Also Metro's policy is to close at it's regular time regardless of when the game ends. You may get stranded if a game runs late.
Metro is the best option if it's a viable option to you. That being said, there is plenty of parking available, for a price! On game days the access is limited, but there are many garages that provide reasonable access to the park. For non-game events (like the OCR next weekend [5/12/18]) driving and parking might be a good option, but game days.... Go for metro!!!
Not really sure, we always take the metro. It's very easy; the navy yard station is a 2 min walk to the stadium.
Expensive but close. I'd rather metro if closer to a metro station. Street parking near the park is prohibited on game day.
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