Geology Site Account

Site name: Beacon Cliff

Grid reference: TM262317

Brief description of site:

Beacon Cliff is a site of geological interest with potential for geological education. Coastal cliff with former exposure of Red Crag and London Clay. Site of considerable historical interest.

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Summary of geological interest

In 1704 the naturalist Samuel Dale described a cliff of sand containing fossils at Beacon Cliff, Harwich that appears to be the first record of the East Anglian Crag deposits in the scientific literature. The fossiliferous sand is now known as the Red Crag but unfortunately this exposure, which lay on top of the London Clay, has now been lost due to coastal erosion.

A fine illustration of this cliff was published in 1730 in Samuel Dales The History and Antiquities of Harwich and Dovercourt which was the first book to describe and illustrate fossils from Essex. In 1829 a description of the cliff was published in the Transactions of the Geological Society which tells of a much smaller exposure; and only 12 years later, in 1841, it had almost completely disappeared. In that year Essex amateur geologist John Brown wrote that the Red Crag œis so reduced€¦.by the action of the waves that only by close attention can it be traced€. By 1877 the Geological Survey memoir stated that €œa few fragments of shells at one spot on the top were all that remained€.

Relics of the Red Crag cliff can still occasionally be found on the beach in the form of durable pieces of fossil whale bone and phosphatic nodules.

The recovery of cement stones for cement manufacture from the London Clay cliffs and foreshore hereabouts led to many important fossil discoveries. The stone was dug by hand, which meant that fossils could be easily seen, recovered and sold to passing collectors. Numerous spectacular fossils of early mammals were found in the nodules together with giant turtles and other marine creatures. Many of these fossils went to the Natural History Museum in London but several are in the collections of Colchester, Ipswich and Norwich Museums. Of particular interest was the first discovery in the world of the skeleton of the earliest ancestor of the horse (see separate entry for Harwich Foreshore SSSI).

A fossil dog-whelk from the Red Crag of Beacon Cliff on display in Ipswich Museum. Attached to the specimen is a nineteenth century hand-written label with the words ‘Beacon Hill, Harwich 1815. Photo © G. Lucy