No information here, nor in the book is intended to tell you how to navigate a mountain grade – it is only to give you an idea of the location of the grade as well as how steep and/or how long some of the better-known grades are.

 

Common Sense Rules

 

Sample of Mountain Info in Driver's ABC's

 

A Few of the Well Known Grades in the U.S.

 

Q: What does the (%) percentage mean?


A:  It refers to how many feet you’ll descend per 100 foot of roadway. On a 5% grade, you’ll descend 5 feet per 100 feet of roadway.

 

A grade has a percentage and a length. For example, let’s take a 6% grade that is 10 miles long. This means that for every 100 foot of roadway, you are going to drop 6 feet. For each 1% of grade you’d descend 52.8 feet, since 5,280 feet equals one mile.

GRADE %

LENGTH

FEET DESCENDED

FEET DESCENDED PER 1%

4%

4 miles

844 ft

244 ft.

 

5 miles

1055 ft

 

 

6 miles

1266 ft

 

5%

4 miles

1056 ft

264 ft

 

5 miles

1320 ft

 

 

6 miles

1584 ft

 

6%

4 miles

1268 ft

317 ft.

 

5 miles

1585 ft

 

 

6 miles

1902 ft

 

 

7 miles

2219 ft

 

 

8 miles

2536 ft

 

 

9 miles

2853 ft

 

7%

3 miles

1110 ft

370 ft.

 

4 miles

1480 ft

 

 

5 miles

1850 ft

 

 

Note that the number of feet descended on a 4% grade that is 6 miles in length is nearly the same as a 6% grade that is 4 miles in length. The drop is nearly the same BUT on the 4% grade, the descent is spread out over more territory - making it a less hazardous descent