Cleaners dangled 33m from the road on Tower Bridge as they cleaned the underside of the structure's glass walkways for the first time in 10 years. Footage from the City Bridge Foundation shows rope access specialists hanging from the iconic fixture of the capital city's skyline. Specialist sub-contractors working for the bridge owner abseiled from the twin high-level walkways to clean the exposed underside of the floors for the first time since it was installed. Tower Bridge was built over eight years by five major contractors and 432 construction workers between 1886 and 1894.