If you want to see an amazing aerial view of Washington DC in four directions, the Washington Monument Observatory has what you need! There are 897 steps in the stairwell and the elevator takes you to the top in 70 seconds. From the top, you get a view of the museums and monuments at the national mall, such as the Potomac River, the Lincoln Memorial, the WWII Memorial and the U.S. Capitol Building.
Erected to honor the first President of the United States and surrounded by 50 flags representing the states of the Union, the Washington Monument is 555 feet 5-1/8th inches tall making it one of the world's tallest masonry structures. Indeed, it was the world's tallest structure for about 4 years until the Eiffel Tower was finished in Paris, France in 1889. The monument is about 55 feet wide at the base and around 34 feet wide at the top.
Guided Tour: Free tours of the Washington Monument are provided daily. Visitors can get free, same-day, timed tickets for visits inside the monument at the 15th Street ticket kiosk (located at the bottom of the monument hill). Tickets are distributed on a first-come, first-served basis beginning at 8:30 a.m. until all tickets for that day are gone. One person may pick up to 6 tickets and choose the time for the tour from what remains available for that day. Note: tickets run out quickly on weekends.
You can also get advance tickets online at recreation.gov through the National Park Service Reservation System. All visitors over the age of 2 must have a ticket to enter the Washington Monument. The number to the Reservation System is 1.877.444.6777. Reservations may be made between the hours of 10:00 am and 10:00 pm. The tickets are free, but you will have to pay $1.50 per ticket, plus $2.85 for shipping and handling. To save a few bucks, pick up the tickets at the "will call" window at the ticket kiosk on the day of your tour.