Map of caves beneath Blackheath from 1946

Blackheath Caves Craske Report from 1946 found by Subterranean Greenwich and Kent

Brilliant find by Subterranean Greenwich and Kent – an old document precisely defining where the caves are beneath Blackheath.


Here’s the full text from the scans, OCR’d using Google Docs, then tidied up by me (apologies for any typos):

On June 29th, 1946, a large number of members of the Society availed themselves of a unique opportunity of inspecting the Blackheath Cavern. The advisability of closing the shaft, excavated in 1940 with the object of re-discovering the Cavern, had been under discussion by the Greenwich Borough Council, and it had been decided that the time had arrived for this to be done. A final inspection by members of the Council had been arranged, and permission was kindly given for the Society to participate. Many years may pass before this remarkable subterranean relic is seen again; and it is thought that a short description of its history and physical characteristics should be placed on record.

The neighbourhood is rich in underground workings, and it had long been known that a cavern of unusual interest existed at the back of Maidenstone Hill, stretching for a considerable distance under the steeply rising ground known as the Point. Tradition associated this cavern with Jack Cade and Oliver Cromwell; but although all accounts agreed that its origin belonged to much earlier times, the entrance had apparently been lost for a long period prior to the year 1780, when it was accidentally re­discovered by a builder in excavating for the foundations of a new house.

This event aroused widespread interest. “Jack Cade’s Cavern,” as it was popularly called, attracted numerous visitors, and several accounts of its wonders appeared in print. H. S. Richardson, founder of a publishing firm of Greenwich which still bears his name, brought out a book in 1834 entitled “Greenwich: its History, Antiquities, Improvements and Public Buildings,” in which he gives the following description: –

“The entrance was then through a narrow aperture, but a flight of steps has since been made. The Cavern consists of four irregular apartments, in the farthest of which is a well of pure water, 27ft. in depth, they are cut out of a stratum of chalk and flint, and communicate by small avenues; the bottom of the Cavern is sand. From the well at the extremity of this singular excavation, it seems probable that it has, at some distant period, been used as a place of concealment, and the general supposition is, that is was used for that purpose during the Saxon and Danish Conquests, but nothing has been discovered to assist inquiry.”

Other published descriptions were more highly coloured, and less in accordance with fact; a certain amount of propaganda with the object of attracting visitors may be suspected. The Cavern earned for its fortunate custodian a considerable income.

For over seventy years following its re-opening, it was constantly on view to the public, upon of sixpence a head to the tenant.of Cavern Cottage, in whose the garden the entrance was situated.

The earliest patrons appear to have been highly respectable. Elizabeth Helme, in her “Instructive Rambles in London and Adjacent Villages” (Longman, Hurst, Rees & Orme, 1818) considered the Cavern an edifying excursion for young ladies, and gives a vivid description of a school visit in which she took part. Like other writers, she tells of a vaulted chamber with pillars of chalk supporting. the roof, from which a magnificent chandelier was hung, lighting up strange carvings on the walls. Holding aloft a torch, a guide led the way through a long, winding passage to the well chamber, the farthest point to which the excavation extended.

But a different class of patronage was growing, and its visits were made long after the respectable sightseers had gone home. Convivial gatherings and dances were arranged for after dark, and for the entertainment of this kind of custom a “bar” erected, from which drinks of all sorts were sold. Fairy lamps of various colours were used to light up the scene. A ventilating shaft (discovered in 1939) was sunk, and a huge pair of bellows was provided for driving out smoke and other fumes.

While some of the visitors amused themselves by tracing their initials on the ceiling with smoking candles, or carving or writing them upon the smooth chalk walls, others proceeded to play practical jokes for the general discomfort of the company. We are told that on one occasion the stench of burning asafœtida defeated the utmost exertions of the man told off to work the bellows; on another, certain revellers suddenly lowered the chandelier, and plunged the Cavern into darkness. Clearly the concern was getting out of hand; and in either 1853 or 1854, orders were given for the Cavern to be closed. The entrance staircase was accordingly filled up with rubble, and within a short time all trace of it seems to have disappeared. From that time until 1939, the Cavern was not only inaccessible, but first hand information about it faded into vague and misleading hearsay.

By the direction of the Greenwich Borough Council, efforts were made in 1906 to find the original entrance; and Councillor M. C. Matthews, M.A., a former president of this Society, took an active part in collecting data for the search. No success was gained; and a further attempt, made during the first World War proved fruitless. By 1939 authority had been obtained for the Council to begin a systematic search for the Cavern, which it was thought might prove useful as an air-raid shelter. The services of Messrs. Le Grand, Sutcliff & Gell, Ltd., were engaged; and this firm, specialists in subterranean operations, carried out an electrical resistivity survey of the ground under which the was believed to be situated.

After a number of trial borings, a shaft was sunk in the back garden of No 77 Maidenstone Hall; and at a depth of 32 feet, the floor of the excavation began to give way, the workmen finding themselves in a small cavity, which appeared from inscriptions on the chalk to be part of a passage leading to the Cavern.

As it proved impracticable to clear this passage safely, a new one was excavated, the work being carried out under the supervision of the Borough Engineer, who had been entrusted by the Council with the general direction of these operations.

Blackheath Caves Craske Report from 1946 found by Subterranean Greenwich and Kent

At a distance of about 57 feet horizontally from the foot of the shaft, the original tunnel was again encountered, very close to its point of entry to the main chamber, which was shortly afterwards entered, and found to be dry, airy, and in perfect preservation. The date of entry was October 10th, 1939.

The Blackheath Cavern, as re­discovered, consists of three chambers of the following approximate dimensions:-

The Main Chamber: (max.) 58ft. by 30ft. by l2ft. high.
An Inner Chamber: 27ft. by 21ft. by 6ft. high.
A Well Chamber: 29ft. by 16ft. by 6ft. high.

It will be noticed that these figures, particularly the heights, are not so great as old descriptions led us to expect; but the general plan of the Cavern was confirmed by reference to a survey map made by John Dugleby, dated 1790, preserved the Greenwich Public Library, also by a map in the possession of Morden College. From these it was evident that no part of the Cavern remained hidden. Nor did it seem likely that any alteration had taken place in the floor level: since the innumerable pencilled and incised inscriptions on the walls were at normal eye­level. Most of these inscriptions merely record the names and addresses of visitors, with dates, but a few give further interesting details, e.g. :

J. Johnson. The day before the marriage of Queen Victoria.
All you that come into this place, take my advice I pray: Get some ginger brandy at the Bar

The “Bar” was a roughly built wall of rubble, at the back of which we found fragments of bottles, corks, jars and fairy lamps.

There are a few notable carvings in relief on the walls, one of a large head representing the Devil (with pair of horns), a smaller head, beautifully modeled, of which a plaster cast has been taken, and an incised head, which I think escaped our notice until pointed out by a member of the Society on this final visit. In the ceiling of the main chamber there was a brass pulley wheel, from which the chandelier was doubtless suspended; and a ceiling hook, probably for a lamp, was found in a short inclined passage encountered during the excavation of the tunnel. Near this passage was an iron pipe, about 8 inches in diameter, evidently the lower end of the old ventilating shaft. No trace was found of the chalk columns, but these were probably taken down and used to block up the original entrance. The exact position of this entrance with reference to the garden of Cavern Cottage cannot be plotted with certainty, on account of the re-development of the land, the rearrangement of the garden boundaries and the demolition of the Cottage itself.

The inner chamber, which is simply a small extension of the Cavern, has a very low flat roof of flint and chalk, and contains the earliest inscriptions we were able to find. The figures “1780” are clearly readable, and it will be remembered this was the year of the earlier re­discovery. A careful search for traces of a previous occupation revealed nothing, and no evidence could be found to associate the Cavern with Jack Cade or any other historical personage.

The well, situated in a remote chamber approached by a narrow winding passage, is a circular shaft lined with red brick for a short part of its depth. It was quite dry when we found it, a fact attributable to the fall in the level of the water table since 1854. In this chamber, names and dates are closely packed together on the walls; and every angle of the passage wall has been rounded and polished by the streams of visitors, who evidently found this feature the most thrilling exhibit in the Cavern. It is remarkable that pains had been taken, at the final closing down, to block up the mouth of this passage, so that no one, even if he succeeded in getting into the main chamber, could possibly find the well. Had it not been for the old descriptions, and the accurate plotting of this passage on the old maps, the well chamber might easily have remained undiscovered.

Messrs. Le Grand, Sutcliff and Gell arranged for their geological adviser, Dr. Buchan, to examine the Cavern, and in his report he commented upon the absence of tool marks, which he thought indicated that the excavations had been made when the only implements available were those of wood or horn, used as levers to get the chalk out in blocks. He concluded: “The reason for the various caves in Essex and Kent has not been fully established, but it is probable that some (dene­holes) were used as hide-outs during early invasion when the enemy approached by the river, while others were probably flint mines.

The writer of these notes was a member of the Borough Engineer’s staff during the operations which led to the re-discovery of the Blackheath Cavern; and it is due to this fortunate circumstance that he was able to make personal observations at every stage of the work, and keep records. Other references to the subject will be found in the publications set out below.


The Underground Passages, Caverns. etc., of Greenwich and Blackheath. M. Stone, M.A. Greenwich Antiquarian Society, 1914.

Hart’s History of Lee. Kentish Mercury, May 18th, 1906.
A Survey of Maidenstone Hill. (Map) John Dugleby, 1790.
London South of the Thames. Sir Walter Besant.
Instructive Rambles in London and the Adjacent Villages. Elizabeth Helme. Longman, Hurst, Rees & Orme. 1818.
Greenwich: Its History, Antiquities, Improvements and Public Buildings. H. S. Richardson. 1834.

Thanks are due to Messrs. Le Grand, Sutcliff and Gell for permission to use the photographs taken by Mr. Sydney Newbery, of 7 Stockwell Terrace, S.W.9.

The Society would also wish to record its appreciation of the courtesy of the Greenwich Borough Council, in giving facilities for the Cavern to be inspected.

Caverns at Blackheath

This is probably another cavern under Blackheath and not the one described by Mr. Craske.

Extracted from the Minutes of the New Cross Turnpike Trust. Oct. 28th, 1797,

It being stated to the meeting that within a few days past a great part of the Earth underneath the Road leading from Blackheath to the Limekilns on the North side had given way and with a part of the Road had fallen in a very considerable depth and that from the appearance of it more was likely to fall in owing to a large Cavern or Excavation beneath the Road, whereupon several of the Trustees present went to the spot to view it and having seen the same and made Enquiry of some persons who were said to have explored the Excavation, it was proposed that a shaft or well should be dug in some part of it and the Cavity filled up with the earth from the adjoining Bank and be rammed in both perpendicularly and horizontally so as to make the whole solid and secure, but Mr. Driver and General Davis, two of the Trustees present, offering to explore the Excavation on Monday next, it was


That if upon Examination the plan proposed shall appear to be the most effective that it be carried into Execution, but at all events that immediate care be taken to prevent any accidents happening from the falling in of the Road and the Meeting agreed to adjourn to this day Sennight to give such further Directions for securing the Road against further Damage and the Public from Danger as may be the more speedy and effectual, and the Meeting is hereby adjourned accordingly.
Nov. 4th, 1797.

General Davis and Mr. Driver reported that they had examined the Excavation under the Road leading from the lime kilns to Blackheath, that it runs in a southern Direction 33 ft. then turns south­west 33 feet 6 inches, then to the north 47 feet to the centre of a part which rises higher than the rest in the form of a Dome; that the average width is from 15 to 19 feet and about 12 feet on an average in height. They also reported that a shaft had been sunk at the Dome where the Earth was not more than 8 feet to the surface the Road.


Filed under blackheath, history

7 responses to “Map of caves beneath Blackheath from 1946

  1. Pingback: Cave Map overlaid on Google Earth | The Blackheath Bugle

  2. Frank Hobson

    I think you will find that, although the words are the right way, round the map is ‘flipped’ horizontally. The Bluecoat school is to the East of Dutton Street not the West.

  3. Frank Hobson

    re my earlier comment. Appologies, the map isn’t flipped – it’s just not where you put it on your Google map. It is the part of Maidenstone hill that is almost at Blackheath HIll. See the same map at

  4. Lee Cheshire

    There is a mistake on the original map – the street marked ‘Dutton Street’ is actually Dabin Crescent. The street numbering is still the same. The church and school are not there any more, replaced by the large building on the junction of Maidenstone and Blackheath hills.

  5. Frank Hobson

    As discussed above, the original map had mistakenly labelled Dabin Crescent as Dutton Street. See Google map for where Dutton Styreet actually is. But setting off on my walk this morning I noticed that Dutton Street is now signed as Maidenstone Hill! In other words there are now two Maienstone Hills. Lets hope postie can cope

  6. Elaine pooke

    I was told that blackheath was a chalk mine with pot holes by a reputable person at English Heritage.

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