I train on basically flat terrian too. I try to find inclines to practice running up and we even found a new park this fall that has more inclines.
I wanted to give you the Half Marathon Mile marker for that 1st hill on the way back to Epcot.
You will see the mile 10 Marker, cross under the bridge and then start up the ramp on your right which will curve and tilts a bit. Mile 11 didn't seem as bad, it seemed to be over faster than 10. The next incline finishes with the Mile 12 marker at it's base . You will see it coming as you are able to see the traffic going under it and you do a quick turn back to it and head up. Again it's a pretty quick up/down but it is leading you to Mile 12 Marker so your legs might not be as understanding on any of these 3 markers. LOL
From Miler Marker 10 on in just focus on YOU ARE SERIOUSLY ALMOST THERE! 3 Miles, piece of cake for you. The crowds are waiting, the photographers are waiting in Epcot so get those smiles ready and most importantly ...... the W tent is waiting with Wishers to welcome you home!!!! oh yes there is this piece of medal you get to pick up at mile 13.1
Can't wait to see everyone on the course!!!! Safe training wishes to all for the next couple of weeks. (well always but even more so now).
Regardless of which course, 5K, HM, Full, Goofy....POSITIVE THOUGHTS!!! SEE yourself doing the course, finishing the course!!!