## Creating an objective trail difficulty score for the worlds treks

In Uncategorized by Bill Bailey / December 12, 2016 / 0 comments

The difficulty of the trail as always been on my mind as one of the main pieces of information to include in trek descriptions. This would help anyone looking for a trek to decide if they are physically up for the trek or not. Trek difficulty, however, doesn’t seem to have an objective calculation yet. While researching, most of what I found either scored treks based on opinion or on too little factors. For example, most calculations were based on distance and elevation gain while not taking into consideration average altitude. So I created a formula that was based mostly on the trek data and very little on opinion so as to make the scores across the treks more objective. This score you’ll see on the site as GOATS.

### Calculating The Trek Difficulty (GOATS)

The GOATS acronym was totally by coincidence. The factors in order of how much they weigh on the difficulty of the trek are

- (G)radient : 40{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} of the score. This is how much climbing you do/distance spent climbing. In other words the how steep a climb the trek averages out to be. A trek can start at 1000m and ends at same 1000m but you still do a lot of climbing between the start and the end. This takes that into consideration.
- (O)veral distance : 20{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} of the score. The longer the distance the more difficult the trek.
- (A)ltitude : 20{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} of the score. The higher the altitude the more difficult the trek.
- (T)emperature : 10{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} of the score. A bit different from the others. I set a base line of 17-19℃ (62-66℉) as being the perfect temperature for trekking. Then for each increase or decrease in temperature outside that zone the difficulty increases. So the higher the temperature as well as lower the temperature the more difficult the trek is.
- (S)ignage : 10{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} of the score. The most subjective piece of info in the score but does not weight heavily. The less signs the more difficult the trek.

So those are the factors. The signage factor does not impact the physical difficulty of the trek but it does affect how difficult the trek is by way of navigation. Now to put them together in a formula. To make the calculation easier each factor gets evaluated down to this 5 points scale. The lower the points the easier the trek.

#### Gradient

VALUE | POINTS | WEIGHT | SCORE |
---|---|---|---|

Less than 3{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | 1 | 40{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | .40 |

Less than 6{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | 2 | 40{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | .80 |

Less than 9{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | 3 | 40{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | 1.20 |

Less than 12{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | 4 | 40{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | 1.60 |

Less than 15{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | 5 | 40{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | 2 |

#### Overall Distance

VALUE | POINTS | WEIGHT | SCORE |
---|---|---|---|

Less than 15km | 1 | 20{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | .2 |

Less than 30km | 2 | 20{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | .40 |

Less than 45km | 3 | 20{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | .60 |

Less than 60km | 4 | 20{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | .80 |

Less than 90km | 5 | 20{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | 1 |

#### Altitude

VALUE | POINTS | WEIGHT | SCORE |
---|---|---|---|

Less than 2500m | 1 | 20{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | .20 |

Less than 3000m | 2 | 20{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | .40 |

Less than 3500m | 3 | 20{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | .60 |

Less than 4000m | 4 | 20{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | .80 |

Less than 5000m | 5 | 20{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | 1 |

#### Temperature

VALUE | POINTS | WEIGHT | SCORE |
---|---|---|---|

17-19℃ | 1 | 10{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | .10 |

Less than 17 | greater than 19 | 2 | 10{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | .20 |

Less than 14 | greater than 21 | 3 | 10{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | .30 |

Less than 10 | greater than 24 | 4 | 10{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | .40 |

Less than 5 | greater than 27 | 5 | 10{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | .50 |

#### Signage

VALUE | POINTS | WEIGHT | SCORE |
---|---|---|---|

Signs everywhere
You wont get lost easily |
1 | 10{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | .10 |

Few signs but well trod route. | 2 | 10{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | .20 |

Hardly any signs. you’ll need route finding skills. | 3 | 10{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | .30 |

No signs. You’ll need map gps and luck. | 4 | 10{8efb76381493adecb99ae55e2d648792a8e3d4c40b23ff356b2ce6ec846cbcf7} | .40 |

#### Example Calculation : The Santa Cruz Trek

**Trek Data** : Total Climbing: 1547m, Climbing Distance: 21km, Overall Distance: 48km, Max Altitude: 4760m, Temperature: -3 to 23℃

G = 1547m/21km * 100 = 7.3 | SCORE = 1.2

O = 48km | SCORE = .80

A = 4760m | SCORE = 1

T = (-3+23)/2 = 10 | SCORE = .40

S = Few signs but well trod route. | SCORE = .20

**Difficulty Score** = 1.2 + .80 + 1 + .40 + .20 = 3.6/5

To have the score be out of ten I multiply by two giving the Santa Cruz Trek a difficulty score of **7.2/10 GOATS**.

Let me know what you think in the comments below.