The good news is that most roads are engineered to a 3% grade.
Climbing steeper hills is always a possibility, even in places like Ohio and Wisconsin.
However, human beings, even exceptional ones, are limited in power output. Most cyclists produce 100 to 150 watts while cycling.
Let’s look at a hypothetical cyclist who weights 175 pounds, rides a 28 pound touring bike, and carries 22 pounds of gear and can produce 200 watts of continuous power. These calculations ignore the aerodynamic drag of panniers.
How fast can this cyclist travel while producing 200 watts?
Flat & windless = 20 mph
3% climb & windless = 10.5 mph
6% climb & windless = 6.5 mph
9% climb & windless = 4.5 mph
12% climb & windless = 3.5 mph
15% climb & windless = 2.75 mph