Well, it depends on the running base you have thanks to your soccer.

Part of the training is about gearing your body up slowly for the amount of pounding it takes. So just being in shape from rowing (while it helps you breathe better while running, sure) won't actually help your feet and legs out when you try to cram a full training program into 6 weeks.

I would never tell anyone they can't do it because for all I know, when you go out there to run "for an hour or two," you'll actually make it the full two hours today thanks to your current fitness (and if you do, then hot damn, you're ready for a half-marathon NOW), but based on the fact that you haven't been running since March, 6 weeks is really pushing it and could possibly bring on shin splints, plantar fasciitis, and tendonitis in the Achilles, knees, or hips.

LASTLY: mapmyrun.com lets you choose paths that go off-road. And you can choose satellite view to help you figure out the trails that just look like open land on map view.