A good areal view map website?

I'm looking for a website that shows areal views of the UK in good detail, until recently i have been using Google maps, Yahoo maps, MSN Live Maps and Multimap.co.uk these are usually quite good but i'm currently looking for an area that none of these site show in good detail. Google and Yahoo maps both only go to county distance any closer and i get the message 'we dont have the imagery to zoom to this distance' multimap doesnt zoom in close enough, and MSN Live maps zooms all the way in but it is very blurry and i need detail in the image.