Mercia TREC Club - English club that practices TREC, a competition that is a combination of orienteering on horseback, and maintaining set speeds (normally trot or walk). - http://www.chd-solutions.co.uk/trec/
TREC UK - Information about the sport of TREC, which includes mounted orienteering, and discussion forum. - http://trec-uk.com
National Association of Competitive Mounted Orienteering - A non-profit organization offering information on the objectives of the sport, membership, ride calendar, ride results, chatroom, newsletters, and links. - http://www.nacmo.org/