Google Earth is very useful ....

pussycat

Many a site has special instructions for approach to the sites, ie to avoid restricted village areas, low bridges or narrow lanes unsuitable for caravans etc. We recently went to Longleat where there  has  been a big change to the approach roads there. So 
I went on Google Earth & scanned throught the route at road level, blooming fantastic..what a darn useful thing to do.. Felt quite smug on arrival with an overwhelming sense of  Deja vu.  Have a go yourself its so worth it ...