Warwick Castle is undergoing its annual external clean-up this week, which sees restoration specialists abseiling down its walls to clear weeds and dirt from the 800-year-old landmark.

Building restoration specialists abseil down the walls of Warwick Castle’s south front, known as Caesar’s Tower (Jacob King/PA)

A specialist restorer works high up on Caesar’s Tower (Jacob King/PA)

Weeds were carefully removed from the stonework (Jacob King/PA)

Weeds have sprouted on the stone walls of Warwick Castle’s south front since its last clean-up (Jacob King/PA)

Warwick Castle can trace its origins as a Saxon stronghold to a Civil War prison and stately home. The castle has been a visitor attraction since 1815.

Building restoration specialists abseil from the top of Warwick Castle’s south front (Jacob King/PA)

Warwick Castle undergoes a yearly clean (Jacob King/PA)

The abseiling specialists are trained to work at height (Jacob King/PA)

It is intensive work, all performed metres above the ground (Jacob King/PA)

The castle’s brickwork and towers are cleaned after a year of weed growth and bird droppings (Jacob King/PA)

The specialist restorers carefully make their way down the tower (Jacob King/PA)

A restorer clears weeds from Warwick Castle’s stonework (Jacob King/PA)

Warwick Castle dominates the Warwickshire landscape (Jacob King/PA)