If you are referring to the tour bus that used to go from Mt. Vernon to Arlington Cemetery, not only did they stop that route years ago (along with the one to the Frederick Douglass House), it's now a totally different company that runs the buses. Also, WIMSA (the Women's Memorial) may be closed due to the Federal shutdown.
Are you after tickets for Mt. Vernon? Check their website. If your free tickets for ANC, check their website.
No, there are no tickets except for parking at Arlington National Cemetery. But Arlington House is currently closed for renovations. There is a temporary exhibit at the Women in Military Service Memorial.
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