the training plan Stevie mentioned is on this web site: http://www.halhigdon.com/halfmarathon/novice.htm

for the novice the longest run is 10miles on the Sunday before the race. the advanced tells you to run 2:00hours, i guess it depends on your speed if that's longer than your 1/2 marathon goal.

((i've seen 100mile training plans that have the longest training run is 64 miles. (can you imagine having to dig out that last 36mile stretch on race day?? :)!!))

the marathon training plan i followed had 20miles as the longest training run. i'd seen more advanced plans that had 30mile runs.

i have a running coach now and he is of the philosophy that an hour run with sprints mixed in (paraphrased) which gives you the benefits of a long run in less time.

the Garmin watches aren't water proof enough to swim with :(.