Tobler's hiking function [https://en.m.wikipedia.org/wiki/Tobler%27s_hiking_function https://en.m.wikipedia.org/wiki/Tobler%27s_hiking_function] linked in the '

Tobler's hiking function [https://en.m.wikipedia.org/wiki/Tobler%27s_hiking_function https://en.m.wikipedia.org/wiki/Tobler%27s_hiking_function] linked in the 'See also' section is also very interesting. E.g., says that maximum speed is around 2 degrees sloping downwards and that speed comes down to about a tenth at around 30-40 degrees slope upwards or downwards.