A clock that will run and chime for thousands of years is now being installed deep within a mountain in Texas. The project called 10,000 Year Clock is being spearheaded by the Long Now Foundation and is partly funded by Amazon's Jeff Bezos.

Planning and construction of the clock have been on for over two decades now, Popular Mechanics reports. The assembly is now being completed and Bezos released footage on his Twitter that shows mechanical parts of the clock being put together.

The clock will run for thousands of years without any human intervention and is entirely mechanical. Designed by Danny Hillis, the clock will also ring out chimes once every 1,000 years and this will be a unique, unrepeated chime.

Long Now organisation's website says there is no set opening date for the clock just yet, but parts are being machined and the assembly has started. "I want to build a clock that ticks once a year. The century hand advances once every 100 years, and the cuckoo comes out on the millennium. I want the cuckoo to come out every millennium for the next 10,000 years," said Hillis on the project when it was first envisioned in 1995.

Bezos, who is considered to be the richest man in history, is one of the primary funders of the clock. He has reportedly put nearly $42m (£30m) in the project. He, however, had no say in the design and build of the clock.

At 200 feet tall, the clock will be massive, but mostly buried inside a mountain. It will be powered only mechanically and will also make use of heat from the Sun. Made entirely out of Marine grade 316 stainless steel, titanium and dry ceramic bearings, the clock is expected to run smoothly with minimal deterioration for its entire lifetime. The decision to use ceramics was made after the builders realised that ceramics simply last longer than metals, can be made harder than metal bearings, and they need no lubricant to function. They are also smoother and a better option for slow moving parts, notes Long Now.

Once completed, visitors will be allowed to see firsthand several of the clock's mechanisms from designated viewing areas that will be built into the clock. Yearly anniversaries, as well as 10th year, 100th year, 1,000th year, and 10,000th year anniversaries will be observed at the clock, if there are people around to witness it.