The best holiday we've had was in Wooler. A small community in the far north of Northumberland.
Our children were about 12 and 9.
The beach around Bamburgh was so stunningly beautiful and quiet.
Wooler was a lovely village.
Lots of boat trips available to the Farne Islands to see puffins, seals and other wildlife.
Lindisfarne , touristy that it is, was still quiet enough to enjoy... local mead, history and great rock pools , but mind the tide!
Alnwick Castle is fantastic for young families. The tree house is amazing !
Bamburgh Castle is wonderful.
Just being within the Cheviots was fantastic in itself.
Ok , I might be biased.
Other than that, Pembrokeshire was just as fantastic as was Machynlleth in Snowdonia. .
Near Machynlleth there is a Scientific recycling centre. Not sure what the name is, ( I'll Google) but it was the best day out . We saw pamphlets at our holiday cottage but dismissed as naff.
Our holiday there was beset by bad weather and on our last day thought that we'd just pop along.
It was great and the children loved it.
The Centre for Alternative Technology, I believe.