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Tour Information for USNO Washington DC

Updated 2017 September 1

Public tours of the U.S. Naval Observatory in Washington, DC, are available, but on a limited basis. They may be canceled at any time with little notice.  Please read the tour policy and admission procedure below.


We are accepting applications for tour spaces in November, December, and January 2018.

Public tours of the USNO are offered on selected Monday evenings from 8:30 pm until 10:30 pm EDT (7:30 pm until 9:30 pm EST after November 4), except on Federal holidays. Tours will include a presentation of the Mission and History of the Naval Observatory, a description of of USNO's timekeeping responsibilities with a presentation on the history of precision timekeeping, and (weather permitting) viewing of celestial objects through the historic 1895-vintage 12-inch Alvan Clark refractor telescope with an astronomer. We generally try to schedule at least two tours per month. Tours take place "rain or shine"; however they may be cancelled if the weather is hazardous.


Please be aware that USNO is a military installation.  Public access is limited to the designated tour nights and tours may be suspended at any time and with little notice by military security and/or other considerations.

If a specific Monday doesn't fit your schedule, or if you would like more options for telescopic viewing of astronomical objects in the Washington area, be sure to check our page of links to local Observatories, Planetaria, and amateur astronomy groups.

Individual and group tour passes must be reserved in advance for every Monday night tour. You must provide the names and dates-of-birth of all individuals in your party. An individual requester can apply for a maximum of 20 spaces for an organized group. As a Requester, you must also provide an e-mail address (required) and an optional daytime telephone or FAX number so that we may contact you with the status of your request. Your request will be processed in the order in which it was received. You will receive an e-mail or telephone confirmation when your order has been processed no later than the Friday before your First Choice tour date. If you have not received a confirmation notice by this time, you may assume that you are NOT on the name list(s) for your requested date(s). We will make every effort to try to contact you to schedule a subsequent date.

All adult visitors are required to present a valid government-issued photo ID (CAC, Passport, Driver's License, etc.) that matches their name and date-of birth before they are admitted to the grounds. Visitors who do not have a confirmed reservation will not be admitted under any circumstances.

All visitors must enter the grounds via the Observatory's South Gate, located at the end of Observatory Circle near the Embassy of New Zealand.  No vehicles will be permitted on the base.  There is ample free on-street parking available outside the gate.

Please leave backpacks, bags, weapons, and any bulky items in your vehicle, as they will generally not be permitted on the grounds.  Please line up outside the gate and obey all instructions from the security personnel.  Cameras are permitted on the grounds.

All visitors must be prepared to submit to a security screening. This will involve passing through a magnetometer and the hand-searching of personal belongings. Security screening will begin at 8:00 pm EDT (7:00 pm EST after November 4); please be present at the gate by this time. Visitors who arrive after 8:20 pm EDT (7:20 pm EST after November 4) will not be granted admission even if they have a reservation.

Refusal to accept these terms will result in denial of admission.

Once on the grounds, all visitors will be issued a Visitor's Badge. This badge must be worn at all times, and must be surrendered at the conclusion of the tour.

There is considerable walking on hilly ground in darkness during the tour. Please take this into consideration before you request passes. Many of our buildings are old and do not have easy access for wheelchairs, strollers, etc. Once on the grounds visitors will be placed into escorted groups. You must stay with your assigned group throughout the tour.  While you are certainly welcome to bring them, tours are not recommended for children under the age of 10 years.

Click here to submit a reservation request

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