Best way to get from Seattle to Boston for matches?

Hey everyone, I've got tickets for a game in Seattle and another in Boston two days later. What's the best way to travel between the cities? Flight, train, or rent a car?

Flying is fastest if you can swing it, but Amtrak is a great scenic option. The cross-country routes are comfortable and you can see a lot of the country. Book in advance, it'll sell out for sure during the cup.

I'd rent a car if you want flexibility to stop at things along the way. It's a long drive though—about 3 days. Flying is probably your best bet for time.