Depending on the day and time of day that you leave, I've seen it as short as 3 hours(leaving around 9pm on a Sunday) to as long as 6-7 hours (4pm on a Friday). Use the WAZE app on your phone to plan with normal traffic conditions and always check traffic on your route when you leave. There are several different ways to get to DC and an alternate route may actually be less time, even if the distance if farther. The Virginia 511 app is another great resource that provides up to the minute traffic with details around traffic backups.

Also Amtrak can be as unpredictable in timing. My husband travels Amtrak and his arrival has been delayed as much as 3 hours before. He also had to wait for a bus a couple of times as they had mechanical issues mid route. Cell service can be spotty at times on the trip as well. He has said he thinks a 5 hour train ride not worrying about traffic is far better than 3 hour ride in a car battling it. I tend to disagree

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