Hey, Reader

Ever wished you could head out for a walk in the hills and predict how much time it'll take with some degree of accuracy?

In this post, I will share a pretty cool technique that'll turn you into a map-reading virtuoso. Your friends will marvel at how you effortlessly arrive at the pub right on schedule for that well-deserved pint.

So, let's jump right in.

Naismith’s Rule, what is it and how can it help you?

Naismith's Rule is a practical guideline for working out the time required to walk a predefined route, factoring in both distance and elevation changes.

Devised by Scottish mountaineer William Naismith in 1892, this rule of thumb is still used as a useful guideline for hikers with a reasonable level of fitness walking typical terrain under normal conditions.

The basic rule is to allocate 1 hour for every 3 miles (5 km) of forward movement, with an additional ½ hour for every 1000 feet (300 m) of ascent. Since those early days, the rule has been extended to hikers carrying medium or heavy loads.

• For those with light loads, allow a base speed of 5 kilometres per hour (12 minutes per kilometre), with an added 1 minute for every 10 meters (or contour crossed) during ascent.
• When carrying medium or heavy loads, allow a base speed is 4 kilometres per hour (15 minutes per kilometre), with an added 1 ½ minutes for every 10 meters (or contour crossed) during ascent.

It's important to note that the rule assumes a contour interval of 10 meters. If the contour interval on a map varies, adjustments should be made to the time added for each contour crossed.

For instance, OS Maps may feature contour intervals of 5 or 10 meters, depending on the specific map. Harvey maps, on the other hand, might include a contour interval of 15 meters in certain editions.

Before heading out, I would advise you to check the contour interval for your map to ensure accurate time calculations.

While often referred to as a "rule," these calculations are more of a guidance for estimating journey time when heading out into the outdoors.

I teach Naismith’s Rule in all my navigation courses and get the students to practice throughout the course. It’s a great technique to learn, and over time you will get better as you fine-tune your walking speed across various terrains.

Next time you head out for a walk give it a try and see how you get along. At the end of the day, all these skills take time to master. So, embrace the journey, enjoy the process, and happy hiking.

Aaron.

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