Historic England https://historicengland.org.uk
Avon Industrial Buildings Trust http://aibt.org/home.html
Images of England is a ‘point in time’ photographic library of England’s listed buildings, recorded at the turn of the 21st century.
You can view over 300,000 images of England’s built heritage from lamp posts to lavatories, phone boxes to toll booths, mile stones to gravestones, as well as thousands of bridges, historic houses and churches.
The site brings together the English Heritage online “list” of listed buildings, The “Images of England” website (which also includes most listed buildings but also has pictures of some) and the “pastscape” site which has archeological records. All of these were available before but it is nice that they are in one place.