Calculating Hiking Times

Blog Post created by mmckeanesriaustralia-com-au-esridist on Jan 30, 2020

One of the most basic human functions is to navigate from a starting point to a destination, a task that is completed by all humans’ countless times across their lives and throughout human history. Despite the simple premise, estimating the time required to travel on a trail or cross-country on foot is a complicated process owing to the many different factors and circumstances involved. This blog will brieflydiscuss three methods or calculating hiking times; Naismith’s rule with Langmuir’s Decent Correction, Tobler’s Hiking Function, and The Adjusted Tobler's Hiking Function. These methods have been established as ways to estimate human movement between two points using models based on algorithms that are commonly incorporated in Geographic Information Systems.

If you are interested in applying any of these methods to you own analysis please reach out and I would be more than happy to provide additional details on calculating each method in ArcMap and ArcGIS Pro.

Naismith’s rule with Langmuir’s Decent Correction

Naismith was a Scottish Mountaineer and in the 1800’s devised a rule to calculate hiking times for the average male with average fitness on easy expeditions. His rule stated that it would take one hours travel for every three miles (5 kilometers) on the map, with an additional hour for every 2,000 feet (600 metres) of ascent. While this rule is considered to be a fair indication of travel time and is still in use among expeditioners today, it does not take into account travel time on negative terrain. Langmuir, another accomplished mountaineer and outdoorsmen, proposed the following correction: Subtract 10 minutes per 300 meters of descent between 5 and 12 degrees and add 10 minutes per 300 meters when descending slopes greater than 12 degrees.

Tobler’s Hiking Function

Tobler’s Hiking Function estimates speed taking into account the slope and its direction. It states that travel is at 6 kilometers per hour at -5 percent slope, with speed exponentially decreasing as the slope increases. Tobler’s Hiking function calculates hiking speed slightly faster for downhill travel that uphill on the same slope. Tobler’s Hiking function is widely used and is believed to be the most prevalent model used in least-cost path analysis.