Malham Cove
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Malham Cove is a natural limestone formation, known as a national beauty spot, near Malham, North Yorkshire, England. It comprises a huge, curved limestone cliff at the head of a valley, with a fine area of limestone pavement at the top.
Adam Walker described the cove thus in 1779:
| “ | This beautiful rock is like the age-tinted wall of a prodigious castle; the stone is very white, and from the ledges hang various shrubs and vegetables, which with the tints given it by the bog water. & c. gives it a variety that I never before saw so pleasing in a plain rock. | „ |
Originally, a large waterfall flowed over the cove as a glacier melted above it. The remnant of a stream which once fell over the cliff flows out of the small lake of Malham Tarn, on the moors above the cove. The stream now disappears under the ground at the aptly-named 'Water Sinks', several kilometres before its valley reaches the top of the cove. A stream of similar size emerges from a cave at the bottom of the cove, and it was for many years assumed that the two streams were one and the same. However, experiments with dyes have now shown that this is not the case. Rather two streams go underground at different locations, cross paths without mixing behind the cliff, and re-emerge many miles apart. That this is possible testifies to the complexity of the system of caves behind the cliff, which is thought to be around 50,000 years old.
The lip of the cove has been more heavily eroded than the sides, creating a curved shape. A colossal amount of water used to flow over this waterfall, which measures 80 m high and over 300 m wide — some experts[citation needed] say that the flow would have been about the same as that of the Niagara Falls today. However, nowadays the limestone does not get sufficiently saturated for the fall to become active. The last record of water flowing over the fall in any kind of volume dates back to the early 19th century after a period of heavy rain.
The Cove (and nearby Gordale Scar) were featured on the TV programme Seven Natural Wonders as one of the wonders of Yorkshire.
The valley was formed at the end of the last Ice Age when the ground was frozen and the usually porous limestone was made impermeable. The frozen ground meant that meltwater from the melting ice sheet formed a large river flowing over the surface and this eroded the valley that we see today. The water from this river flowed over Malham Cove to form a huge waterfall. When the climate warmed around 12,000 years ago the ground thawed and the river in the valley disappeared underground leaving the valley dry as we see it today.
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