As you get used to it you will be able to walk faster, and longer, in that same 10 minutes. Stop by NYS Office for Aging's site for more on walking for fitness. Well Hiking might just be up your alley. Or hill, as the case may be. You will need to dress right.
Water is a definite necessity.
Make sure it can hold enough water for the hike, plus a little extra. Not that I expect it, but it is possible to get lost. Also bring some trail mix for extra energy. Maybe even one or two energy bars. Just in case.