Crikey. A lot of Scottish islands as well as Dutch and Danish ones. Also Anglesey and Wight.
Let me think ...
... I'd say more than 20 including such islands as Anglesey, Lismore, Tiree, Islay, Rousay, Papa Westray, Fetlar, Unst, Vlieland and Fano. We're trying to nail it down now as you've got us thinking about it.