I've done the 5k, the 10k, the half and the whole all at DW in four consecutive years. I will tell you what I looked forward to was looking forward to seeing someone I knew at a pre-designated spot! This year they've changed the half course to begin/end at Epcot. There are a couple spots along the course you can get in either multiple viewings of your relatives or a single good one.
First is to see them as they go down Main Street USA in the MK. This is between mile 5-6 so depending on their pace you can reasonably guess when they will come through. When they shoot off the gun at 6 a.m. to start the race it can take up to 10 minutes before you cross the start line so if they do a 10-minutes pace they should go down MS about 7 a.m. (5x10+10). They open MS early to the hub but no further. When I ran I stopped for a quick picture with family then kept going. You can jump the monorail back to Epcot to see them at the finish or drive(?).
Second is the parking lot area out in front of TTC and Poly. Runners will loop through the TTC parking lot on the way to MK (about mile 3-4) and then have to come back up the road by the Grand Floridian and Shades of Green/Poly later. Good thing is you get to see them twice but bad is you probably won't make it back to the finish line in time. Again, estimate the pace. The runners are like ants but if you are looking for someone (and they are looking for you) it is a great pick-me-up.
Third is as the runners go under the road (where the trams go) in front of the TTC you can see the runner there and then hop the monorail back to Epcot and see them at the finish line.
Fourth, if you can't get in the MK you can ride the monorail to the Contemp at mile 5 go out to the road in front (on the MK side) and cheer the runners on as they go under the water way and up the hill to the MK.
Don't stop on the road on the way back & forth betweeen the toll booths to MK and the Epcot road. It's about 4 lanes in each direction, trafficy, cars blowing horns, and windy.
It's great fun, great to finish, but I didn't feel like my family had to be there at the finish. It is fun to find them at their appointed place along the course where I expected them. That's the main thing. Thanks for supporting them!
Bama ED
