11 October 2011 is the 460th anniversary of the 13th Session of the Council of Trent.

The thirteenth session was held on 11 Oct., 1551; it promulgated a comprehensive decree on the Sacrament of the Eucharist (in eight chapters and eleven canons) and also a decree on reform (in eight chapters) in regard to the supervision to be exercised by bishops, and on episcopal jurisdiction.   (http://www.newadvent.org/cathen/15030c.htm)