HemsWX, made by pilots, for pilots 
I see Denmark is also included now, and some parts of Sweden.
Autorouter – via telegram. You type ‚webcam LOWZ (as an example) and you get the images. But you’re right, not always available
This sort of facility needs constant testing and re-coding, and if possible pilots reporting issues (most won’t especially if the contact is not easy or obvious, or their language differs from the site developer’s).
One could automate the testing, by grabbing each one say every day and checking if a valid jpeg is returned. I would think sites like Windy must have done that, otherwise that functionality would be mostly useless, after some time.
Also this source:
“Airport Web Cams”:
https://www.flyingineurope.be/Airport%20webcams.htm
One thing to really watch out for on webcams is that they are actually current: the best ones are the ones running real-time streaming video with a timestamp, when you can see things moving about and a valid timestamp you can be reasonably confident that you’re seeing the current situation.
About 90% of the webcams I search for when wanting to cross the Welsh, Scottish or Cumbrian hills show an image but it’s not updated since some time in the early 2000s – so you have to be really careful to check the timestamp is showing something current and valid or you could be mislead by an image more than a decade old.
alioth wrote:
One thing to really watch out for on webcams is that they are actually current
I went by car to a gliding club when the nearest CAT airport was hardcore IFR, webcam showed sunny day and a full cross-country grid
Autorouter also has access to some airport web cameras.
Thought I posted a picture here. Anyway we have this HemsWX, with special purpose web cams. It’s made by and for ambulance helicopters, but is free to use by GA pilots. They are much more than just web cams, as they have direction and overlays showing distances and what perfect visibility should be like. It’s also a weather app.
[ you did post it in another very similar thread, and now the two have been merged, so your map is now above ]
FYI, HemsWX requires registration before one can use it. I tried to register and was denied on the basis that it is only available for Hems and SAR institutions (not individuals) based in Denmark, Norway, or Sweden.
