ANCIENT MYSTERIES :.

INVESTIGATION INTO MYSTERIOUS CAVERN UNDER SOUTH LONDON

  Posted Sep 7.03

Original headline: Looking into Blackheath's mysterious cavern

Parkman's, the surveyors who investigated a six-foot-wide crater that appeared in the A2 at Blackheath Hill last April has said further checks on land stability in the area are needed.

Decisions on their report were to be made by Greenwich council last night.

But the council, which would apply for a grant from English Partnerships to cover the costs of the investigation, is not yet sure how much it will cost.

The collapse of the A2 into chalk pits after subsoil washed away triggered traffic chaos, hundreds of people were evacuated from their homes, and repair work spanning nine months cost £2.25million.

Honeycombs of chalk workings are known to exist under Blackheath, and rumours and stories about one of the largest, known as the Blackheath Cavern, located below The Point, have circulated for centuries.

The ancient chalk workings are said to have been shelters for the Saxons and later for 15th century rebels. Rediscovered in 1780, the cavern became a tourist attraction and a venue for wild parties but were closed down hurriedly in 1854 after a "disorderly masked ball".

Its existence slipped into legend until 1939 when, after attempts in 1906 and 1916, Greenwich council located an entrance using "electrical resistivity" and sank a shaft down 40 feet.

At that time a Kentish Mercury reporter entered the cavern from the back garden of a house in Maidenstone Hill, along with council representatives considering its use as air raid shelters.

He reported there were in fact three linked caverns a total of 59ft long and the floors were littered with broken bottles.

But concern about the stability of the area has resurfaced following last year's collapse.

Greenwich council undertook remedial ground works to stabilise council-owned Cade Tyler House after the road collapse and carried out investigation work around Undercliffe House and A2 where it meets Maidenstone Hill.

In a recent letter to residents, David Jessop, the council's assistant director of transport and highways, said: "Bearing in mind the recent subsidence and some of the recent investigations, I think it is prudent that the condition of the Blackheath Cavern and the extent of any workings in the immediate vicinity are thoroughly investigated."

A council spokesman said: "There is no suggestion of any immediate risk to properties as far as the council is aware.

"It should be stressed that responsibility for the land and buildings upon them is with the relevant property owners. But the council considers it has a wider public responsibility to take a lead in bringing about these investigations."