You will need a car to get to Woodlawn, Gunston Hall, and the other attractions south of Mount Vernon, but you can get to the first president's home by public transportation.
By Car -- It's a pleasant, picturesque drive to Mount Vernon, 8 miles south of Alexandria, via the George Washington Memorial Parkway, which in many places skirts the river's edge. After passing the traffic circle in front of Mount Vernon, the same highway becomes the Mount Vernon Memorial Parkway (Va. 235), which ends at U.S. 1.
By Subway, Bus & Taxi -- It's possible to get to Mount Vernon via Metrorail and connecting bus. Take Metro's Yellow Line subway (tel. 202/637-7000; www.wmata.com), which stops at the King Street Station in Alexandria, to Huntington Station south of Old Town Alexandria. Exit to Huntington Avenue and catch the Fairfax Connector bus no. 101 (tel. 703/339-7200; www.fairfaxconnector.com). The bus ride from Huntington to Mount Vernon takes about 25 minutes and costs $1.35 each way, exact changed required. Call or check the website for the bus schedules. You can also take a White Top Cab (tel. 703/644-4500); fares are about $20 each way.
By Guided Tour -- The Tourmobile (tel. 202/554-5100; www.tourmobile.com) runs from Arlington National Cemetery or from the Washington Monument in Washington, D.C., to Mount Vernon from April through Labor Day daily at 10am, noon, and 2pm. Tourmobile booths at the cemetery or Washington Monument sell tickets. The fare is $32 for adults, $16 for children 3 to 11, free for children 2 and younger, and it includes admission to Mount Vernon. The trip takes about 4 hours; reservations are required in person at least 30 minutes before departure.
The venerable Gray Line (tel. 800/862-1400 or 202/289-1995; www.grayline.com) has all-day guided bus trips from Washington, D.C., to Mount Vernon via Old Town Alexandria. The tours depart at 8am daily except New Year's Day, Thanksgiving, and Christmas and cost $50 for adults, $26 for children 3 to 11.
By Boat -- From April to October, the Potomac Riverboat Company, at Union and Cameron streets behind the Torpedo Factory Art Center in Old Town Alexandria (tel. 877/511-1628 or 703/548-9000; www.potomacriverboatco.com), offers cruises down the river to Mount Vernon and back. They depart Tuesday to Sunday at 11am from Memorial Day to Labor Day, on weekends during May, September, and October for the 1-hour cruise to Mount Vernon. Weekday round-trip fares are $38 for adults, $20 for children 2 to 11, including admission to Mount Vernon. The return voyage leaves Mount Vernon at 4pm, which means you will have about 4 hours to explore the mansion and grounds (not long enough if long lines are waiting at the mansion).
In the meantime, the boat goes on 40-minute photo cruises from the Mount Vernon wharf. Fares are $9 adults, $5 for children 2 through 11. Kids under 2 ride free on all cruises.
Don't Come Early in Spring, Summer, or Any Weekend
You will need at least a half-day to see Mount Vernon and the nearby gristmill and distillery. Many people show up at 8am in spring, summer, or any weekend with the idea of beating the crowds, which they inadvertently create. The guides inside the mansion do not have time to give in-depth information or answer questions when it's crowded. I would tour the mansion later in the day during these busy periods. Rather than stand in line, I highly recommend buying your tickets and reserving your guided audio tours online in advance at www.mountvernon.org. This is especially important during summer and on holiday weekends, when the audio tours sell out quickly. Be sure to click on "Packages," some of which include the price of the audio tour.