Big Ben's famous bongs will be silenced for four years next week as major conservation work is carried out.
The deafening chimes are being stopped to protect workers who are renovating the Elizabeth Tower that houses the Great Clock and its bell.
The bongs will fall silent after sounding at noon on Monday, August 21, and are set to begin again regularly in 2021, although they will still ring out for important national events such as New Year's Eve and Remembrance Sunday.
It will be the longest period Big Ben has been silenced in its 157-year history.
The 13.7-tonne Great Bell was last stopped for maintenance in 2007 and before that was halted for two years in 1983 for refurbishment, but has been stopped on a number of other occasions since it first sounded in 1859.
Steve Jaggs, keeper of the Great Clock, said: "Big Ben falling silent is a significant milestone in this crucial conservation project. As keeper of the Great Clock, I have the great honour of ensuring this beautiful piece of Victorian engineering is in top condition on a daily basis.
"This essential programme of works will safeguard the clock on a long term basis, as well as protecting and preserving its home - the Elizabeth Tower.
"Members of the public are welcome to mark this important moment by gathering in Parliament Square to hear Big Ben's final bongs until they return in 2021."
As well as conservation work to Elizabeth Tower, the Great Clock will be dismantled piece by piece and its four dials will be cleaned and repaired.