80metres? Is that all it is, I'm sure from about 1/4mile to 1 1/4mile it's a climb!
Thenn at 3k on the 10k you have about 50metres rising a bit, before a lovely 3/4mile very steep descent, and then hitting the bottom of the hill knowing you only have 4k left.
The half marathon obviously has the same first mile hill, and then a couple of ups and downs you barely notice, before a pretty steep 1//2mile descent down a nicely Wooded road. After this you have a few hundred meters before a little climb for say 200m, quickly followed by another 200m descent.
The last 6miles look flat but apparently rise by about 100feet which explains why the pacing isn't quite as easy as it should be. Then just after 12miles you have a 50metre slight climb, which hits you a bit at that stage, before a nice similar descent that takes you within touching distance as will now be able to hear the commentator. You then have another 0.8miles to enjoy the river and longingly look over the water longing to finish!!
One last park section and you're there!