Gareeh, are you on about the heavily sealed entrance at Kelvin
bridge (with painted sheets of metal)? There is another entrance with metal palisade fencing by the kelvin
dale end of the botanic gardens. Search a map online or PM me for more details
The entrance you want looks like this....
The entrance that I used was at Ford road and looked like the above picture. There is another entrance but is was a solid sheet of metal and well secured
I Might have to check this out properly
Oh BTW there are other tunnels in glasgow, some are open as well
Mr Sam
P.S. last time I went it was securely locked, would love to know if it is now open...