Some National Trust locations in Britain can now be viewed
via Street View at Google Maps, e.g. Avebury Stones.
I have been to Avebury and can say - at the time of this posting - that the opening scene of that link has you on the wrong side of the highway for a correct start to your journey at Avebury - at least as you start your journey when you are actually at Avebury - so click the map command to go out of Street View and then move the Street View "icon person" over on the other - left hand - side of the street, where you will then see some of the main Avebury stones and those stones that a tourist first sees when he visits the Avebury site and starts to take his walking tour. There are of course megaliths on both sides of the street, so play with your location to see as much of the stones as you can.