Modern Street Maps
An easy to use service which includes aerial photographs of the area as it is now.
An easy to use site
This was initially my preferred site - so you will find references to it on older answers - but I now prefer the others.
[There are other map packages - but a choice of 3 is sufficient at present.]
[For the large scale Ordnance Survey maps from circa 1880 see old-maps]
Page updated July 2007