"...dozens of such observatories..."

Not from what I have seen.

I have spent many hours searching on the web and I have yet to find
dozens of observatories that have been well documented so others can
learn and build on their work.

I have also asked a number of times about mobile observatories on
various discussion groups and have had minimal success with the
responses.

If anyone has GOOD links to observatories that are well documented, I
would love to see them.

Thanks

TMT