The cliffs between Lyme and Charmouth are the eroding front face of Timber Hill; there seems to be no overall name for them—"The Spittles" seems to apply to the upper decks of them, and the eastern part is called Black Ven (sometimes spelt Black Venn). Ven is the dialect form of fen.

Lubricated by water, the soft cliffs keep slipping, as you can see by the jumble of rocks at their feet.

The nearer part, just past the Church Cliff, is where in 1908 the Lyme Volcano erupted. From January onward, smoke and even flames were seen, and apparently reached a climax in June, when national newspapers reported the volcano. On June 10, the vicar, accompanied by "Mr. Cameron of Uplyme, a retired officer of the Geological Survey", went to inspect. What had really happened was that a mass of underground debris—"shales, iron pyrites, and cement stones" plus organic matter—had been saturated by rain and had then (it is not clear in what order) decomposed; been exposed by a landslip; mixed with oxygen; ignited by spontaneous combustion; produced "sulphates, iron oxide and sulphurous acid gas"; slipped from "a second tier of the cliff onto the plateau below". Apparently on the same day, June 10 at 1:15 p.m., a further landslip opened a fissure into what looked like a brick kiln, and the smoke then ceased. Landslips are always happening, but it was thought that this time the cause might have been a small seismic tremor (of which there was no record); or, more likely, people's continuing removal of limestone from the cliff.

many breakwaters

fossils

new slips often happen after a bit of rainy weather

a great danger is when people are caught by the incoming tide, try to clamber to safety on a shore which is itself a mudflow or liable to collapse

For instance in February of 2005 walkers became stuck in a mudflow, called on a mobile phone, and had to be rescued by helicopter. On Christms Eve of 2005 a block of the cliff between Lyme and Charmouth collapsed onto the beach, and the day before a piece a hundred yards on the other side of Charmouth fell. A sign "CLOSED DUE TO RECENT LANDSLIPS" was put up, but hundreds ignored it, rambling with their childre onto the mudflow, which was up to eight feet deep and liquid under an apparently solid surface, so that it acted as a quicksand. One weekend in January four children and an adult were rescued by two off-duty Lyme coastguards, who used the side of a wooden crate as support to reach them. One father went to pull out his child, had to be pulled out himself; another commandeered the crate to go back and rescue his child's Wellington boot, despite cries from his wife that it wasn't worth risking his life for a boot that cost a pound; pieces of the cliff were still crumbling around them.