Just across the Kent border with Greater London, one of the UK’s most unique locations is hidden - Chislehurst Caves. This remarkable place in historic Kent is nestled in the town of Chislehurst, a stone’s throw from Bromley.

The caves are an intricate network of over 22 miles of manmade tunnels, burrowed between the 1200s and 1800s, concealed deep beneath a leafy and unsuspecting slice of suburbia.

Kent’s rich history and culture have been significantly impacted by urban sprawl, and Chislehurst Caves is a prime example of this. Although technically the town and tunnels now fall under London, much of the caves’ history unfolded when the area was part of Kent, making them an integral part of the county’s past.

Ancient Origins, a site dedicated to exploring archaeological discoveries, has delved into the history of the caves. According to them, when the caves first opened to the public in 1900, visitors were informed that parts of the system had been inhabited between 6,000 and 4,000 years ago.

Legend has it that the initial phase of the caves was carved out by druids, before being expanded upon by the Romans and then the Saxons around 500 AD. Ancient Origins reports that one of the earliest historical records of Chislehurst Caves is a 13th-century charter, which mentions their use for mining lime-burning chalk and flint.

There’s also speculation that a prehistoric skeleton discovered in the ceiling could suggest the caves date back to 10,000 BC, when people sought refuge during the end of the Ice Age. However, as far as concrete origins go, the earliest evidence of anyone working or residing in the caves dates back to a 9th-century Saxon charter, which documents mines and lime-burning kilns in the area.

It is reported that at the onset of the First World War in 1914, the caves served as a munitions depot. According to The Heritage Trail, they became part of the Woolwich Arsenal and a railway was installed to transport the munitions through the tunnels.

In the interwar period, the mines were utilised by the Kent Mushroom Company, with the humidity and darkness providing ideal conditions for mushroom cultivation.

During the peak of the Blitz in the Second World War, the caves were converted into an underground city. They became the largest air raid shelter in Britain, housing 15,000 people with a pitch costing one old penny per night.

The chapel space and hospital area are still present today for visitors to explore, along with a fully functioning electric lighting network - making living in the caves less daunting than it might initially appear.