I think there are 15 straining cables to the mast, these cables are used for access by maintenance workers as a "quick" way up the mast, using a special carriage, the slow way up is through the tower ladder, some years ago a lady wanted to go up the mast, very nerve wracking apparently but she made it!
Uploaded to Geograph by chris whitehouse on 5 February 2012
Photo © chris whitehouse, 5 February 2012. Licensed for reuse under this Creative Commons licence