Some bits of the moors up near me are still little enclaves in their own rights, but more movement takes place than used to, with people buying cottages as holiday homes/weekend places etc.
But I do know somone local who says that, a matter of maybe only fifty years ago, when people would 'come down' into town from villages as far away as ooh, five miles or so, they would be difficult to understand because they had their own dialect and accent that the 'locals' couldn't understand.
It's largely died out now. But North Yorkshire does still have its own peculiarities. 'Now then' is a greeting, not an admonishment. The first time someone said it to me, I thought 'what have I done?' But 'now then' just means 'hello'. Often abbreviated to 'now', when two farmers are greeting one another.