We have now got used to readily accessing aerial images from above since the advent of Google Maps and Earth, but in the early and mid twentieth century they were rare. The Aerofilms Company produced a lot of high quality aerial photographs of Britain from the air over the period 1919-1953. The whole collection is now readily available on the
Britain from Above web site and it makes fascinating viewing for history buffs.
For the canal enthusiast there are 1209 images with the tag "canal", including many from Scotland, and there are also many river views notably of the Thames. As canal example I have downloaded and linked to a view of the Grand Union in Lemington Spa. It shows the
Sydney Flavel, Eagle Foundry and the
Gas Works in 1937 alongside the Grand Union Canal.
The details of this image can be found
here.
As a comparison here is a contemporary view from Google. The gas works are long gone but the foundry remains as a factory for
AGA Rangemaster - the historic stove/range connection remains.
Leamington Spa from above 2014
The site has a
Canal History Group and this allows easy access to some good canal images. Many have been annotated. I found the image below from one of their links.
Walkers Boatyard alongside the Grand Union Canal, in Rickmansworth
The details of this image can be found
here.
You may imagine that some of the historically important canal locations must feature in the images. Some do, but many do not, since the emphasis was on photographs that would sell. Images of factories and industrial locations feature a lot along with stately homes, large hotels and important public buildings. It is a matter of pot luck if your particular location features but if it does you should be fascinated.