Historical version 2 of Kenwood House (view current version)
Bordered by Hampstead Heath, Kenwood House contains an art gallery with works by Turner and Rembrandt amongst others.
The gardens include woods, lakes and meadows.
On the English Heritage site, see: Around our regions>London region>Local Property Search and select Kenwood http://accessibility.english-heritage.org.uk/filestore/visitsevents/asp/visits/Details.asp?Property_Id=107
Or for details of the gardens: Conserving historic places>Conservation advice>Historic parks & gardens>English heritage gardens and select Kenwood House from the side menu http://accessibility.english-heritage.org.uk/default.asp?WCI=Node&wce=7892&redirected=1
(If anyone can provide direct links, please do!)