This is what we humans do. We make plaques to commemorate success, progress, the famous and infamous, the lost and the remembered.
Unfortunately the plaque no longer exists: destroyed, as far as I can ascertain, when the sunken gardens had their make-over in 2013. I'm not a staunch monarchist but I wish it had been saved, along with the plaque the Queen unveiled when she opened the Afan Lido, one of Wales' first purpose built leisure centres, in 1965. That too met its doom in the building's demolition in 2013. I'm sure a place could have been easily found for both of them. After all, they represented milestones in the town's history.
Plaques became a bit of an obsession with me after that. Here's one we can still see today.
And here's another plaque that commemorates part of our industrial history.
And one final plaque I found while walking around and researching Margam Park that celebrates a birthday and a life that spanned the 20th century, through war and social upheaval, through the terrible and wonderful advances of technology.
Sources:
The Story of Baglan, A Leslie Evans
http://southwalesbricks.weebly.com/argoed.html
http://www.penmorfa.com/bricks/wales2.html