Since the house is small, only groups of four to six people can visit at a time so there are timed tickets, which can be booked by calling (0909) 482380.

Dated and timed tickets can be bought in advance from (888) 395-0005.

Dated and timed tickets are required, and can be bought by calling (800) 929-5800 (or at the door if available).

Dated and timed tickets are required for admission: (312) 930-4040.

Timed advance-purchase tickets for $8 are recommended.

The Washington Monument Lodge on 15th Street opens at 8:30 am for same day, timed tickets on a first-come, first serve basis.

Dated and timed tickets are available at (302) 777-1600 or (888) 395-0005 or at the box office.

Visitors may also obtain free, same-day, timed tickets to the Washington Monument at the 15th Street kiosk.

The museum is issuing timed $20 tickets that will admit people every half-hour.

But timed tickets will be necessary afterward (except on Fridays from 4 p.m. until 8 p.m., when admission is free).