Sakla
Notes on data, code, and the outdoors

Hiking With Dogs: A Data-Driven Approach to Trail Selection

November 18, 2024 J. Stover

Choosing a hiking trail when you have a dog is not as simple as browsing a guidebook. Terrain difficulty, heat exposure, water sources, and leash regulations all factor in. After years of combining my data background with weekend hikes, I developed a small methodology for scoring trails.

The Variables That Matter

Elevation gain per kilometer is the first metric I look at. Dogs overheat faster than humans, especially brachycephalic breeds. A steep trail in full sun during July can be dangerous. I pull elevation data from SRTM tiles and compute gradient percentiles for each segment of the trail.

Water availability is the second critical factor. I cross-reference trail GPS tracks with OpenStreetMap hydrology layers. Streams, fountains, and lakes within 200 meters of the path get scored. A trail with no water source in the first five kilometers gets a penalty.

Shade and Canopy Cover

Using Copernicus tree cover density rasters at 10-meter resolution, I estimate the percentage of the trail that runs under canopy. Anything below 30 percent cover means you need to plan for early morning starts in summer. Dogs with dark coats are especially vulnerable.

The leash situation varies enormously. In France, national parks require dogs on leash at all times. Some regional nature reserves ban dogs entirely. I maintain a small SQLite database of regulations scraped from prefecture websites. For further reading, have a look at outdoor hiking trails that welcome dogs.

Scoring and Ranking

Each trail gets a composite score from 0 to 100. Water availability is weighted highest at 35 percent. Shade gets 25 percent. Gradient difficulty gets 20 percent. Regulation friendliness gets 20 percent. The formula is intentionally simple so anyone can reproduce it.

I tested this on 140 trails in the southern Alps last year. The top-scoring trails were consistently the ones my dog enjoyed most, measured by pace and rest-stop frequency. Not exactly rigorous science, but the correlation was encouraging.

Tools

Everything runs in Python with GDAL for raster processing and GeoPandas for vector work. The code is ugly but functional. I may release it if anyone is interested. For now the SQLite database covers trails in Provence, the Pyrenees, and parts of Brittany.

One thing data cannot capture is the joy of watching your dog discover a mountain stream for the first time. That part is not quantifiable.

© 2026 Sakla
Statistician, open-source contributor, and occasional hiker. Writing about data, animals, and places worth visiting.