All changes to tower
| Date | Change | Source |
|---|---|---|
| 27 Jan 2012 | 1-8: frame id added; frame info added | John Baldwin via database |
| 21 Nov 2010 | 8: canons, historically important added | John Baldwin via database |
| 20 Dec 2008 | URL amended | Tim Jackson#148 via e-mail |
| 19 Jul 2007 | URL added | Mike Chester via pNBR |