Isn't the cycling distance 180 km? Or is it 180 miles? Either way, if you want to start training for that ... drop into the LD forum, join your local randonneuring club, and perhaps look at participating in a 24 hour race or two.

Links to Long Distance events: http://www.machka.net/links.htm

So the cycling part is quite doable ... for me, however, the swimming and running parts would be an issue.