My wife and I live on top of a small hill and our driveway more or less cuts our property in half. As the driveway descends from the house, it heads north and then curves northeast leaving maybe 40% of the property to the east of the driveway and 60% to the west.
The mountain bike trail that I envisioned starts from the top of the driveway and drops down onto the east side. The fall line of the hill heads more or less north toward a corner of the property that is pretty tight (less than 90 degrees). From that corner, the trail would have to climb back up toward the west, where it would cross the driveway after regaining about half of the total elevation descended from the house. Once on the west side, it would drop again to the lowest point on the property and then climb again all the way back to the top. To summarize, pretty big descent from the house (although not even 100 vertical feet), then climb back up halfway, descend again even further, and finish with a big climb back to the house.
To see if my goal of 3/4 mile with 200 feet of climbing was reasonable, I used Google Earth to draw a relatively random path that sort of followed my general idea. It showed about 2/3 mile and almost 300 feet of climbing. I figured the real trail would have even more turns and therefore be a little longer but would probably have a little less climbing if I laid it out properly. So far, so good. Assumptions confirmed. As they used to say on The A-Team, I love it when a plan comes together. 🙂