Since late 18C: they are not caves but stone mines last worked c.1810; and part of a series of such workings from St. Alhelm's Head to Durlston Head.
Worldwiode, many tens, perhaps a few hundred, of millions of years - as long as there have been karst uplands. Many that formed in that time no longer exist because the landscapes in which they developed have long been eroded away.
Yes, People live in caves all over the world and have been doing so for a very very long time! Don't you think?
No-one can say. Understanding their geology is historically recent but as features of caves they have been known for as long as people have vetured into caves. Some were used in Palaeolithic times, judging by pigment on them, in the cave art.
The earliest they would have started to form would have been when their host limestone formation was upliftedand denuded so that karst processes could begin.
The I in him has a short I sound, as in dim and whim.
There is no way to tell where the first UFO was seen. Sightings seem to go back to when mankind drug his knuckles and lived in caves. But it seems that we have been 'visited' almost as long as we have been.
3 days
The Vikings built Long Cabins from locally sourced wood. The centre piece of the village would be a Viking Long house which would probably been decorated with carved animals and depictions of deities. The Long House would have been used as a communal area.
Open caves will have been known the people living around them for centuries of course, even if no-one explored them. Discovering a cave thatdoes not have an open, obvious entrance is a matter for cavers who understand caves, their geology and the signs of their possible existence behind the boulders and earth choking the entrances. Digging that choke out can be a long-time labour of love - I can tell you from personal experience! Some caves ofcourse are entered from springs,but these are a matter for the cave-diver with the specialist skills to explore them.
Open caves have been known since time immemorial, obviously - Palaeolithic people used suitable local caves for shelter. Serious exploration of caves started in the 19th Century, although a few hardy souls ventured into caves long before that and wrote what to us are rather lurid accounts of bottomless abysses and endless winding passages. For some decades the early explorers concentrated on caves naturally already open but now, most "new" caves in the UK, Europe and the more accessible US caving areas are only discovered by "digging" - clearing natural chokes of glacial till or collapses that hide likely entrances. It's necessary to understand caves and karst processes, and basic geology generally, to be reasonably sure of finding a cave in this way.
Both! The fossils within limestone holding caves are of long-extinct animals, but they had still evolved to the species preserved as fossils.
You walk around her grave clockwise 3 times and say her name Polly Long