Clock of the Long Now
mechanical clock designed to keep time for 10,000 years
The Clock of the Long Now, also called the 10,000-year clock, is a mechanical clock under construction that is designed to keep time for 10,000 years. It is being built by the Long Now Foundation. A two-meter prototype is on display at the Science Museum in London. As of June 2018, two more prototypes are on display at The Long Now Museum & Store at Fort Mason Center in San Francisco.
The project was conceived by Danny Hillis in 1989. The first prototype of the clock began working on December 31, 1999, just in time to display the transition to the year 2000. At midnight on New Year's Eve, the date indicator changed from 01999 to 02000, and the chime struck twice.
The manufacture and site construction of the first full-scale prototype clock is being funded by Jeff Bezos's investment firm Bezos Expeditions, with $42 million, and is on land which Bezos owns in the Sierra Diablo mountains in Texas.
Purpose
In the words of Stewart Brand, a founding board member of the foundation, "Such a clock, if sufficiently impressive and well-engineered, would embody deep time for people. It should be charismatic to visit, interesting to think about, and famous enough to become iconic in the public discourse.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Aug 27, 2026. The linked authority identifier is Q963249. Authority coordinates are 31.448, -104.904. None of the 2 selected statements returned an explicit reference. The first chronological checks are 2018, 1989, 1999 and 2000.
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This entry incorporates text from “Clock of the Long Now” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.