You can kind of see some clone stamping like effects in the area. If you look in the bottom center of the area there are 4 small lakes in a diamond, all the same shape, and 3 of them with the exact same smaller lake below them.
Then go here and switch between the Bing and Yahoo images. In the top left the terrain not blacked out in Yahoo is very different from what Bing has. The rivers on the right side also don't look right either.
Also in the Google maps version you can still see the black behind the brown spot. In the corners you can see straight black lines. That area might have been cut out of the original image that Google scanned.
Yahoo maps just has a blacked out area there, Google seemed to like a brown splotch more than a black rectangle, and Microsoft wanted to be fancy and photoshop it. Whether or not something is there, I don't know. Maybe aliens.
Not exactly in Glasgow but Dunaskin near Dalmellington has plenty of track and some old abandoned trains to check out.
http://www.flashearth.com/?lat=55.342495&lon=-4.451325&z=19.5&r=0&src=msl
Example of what's there: http://imgur.com/WyRaKTu