The title pretty much sums it up..
Trying to figure out how steep is too steep when it comes to roads and sidewalks.

I am working on a world that has some awesome hiking trails through a mountain range, but I'm concerned some of the parts may be too steep.
I looked at the routing data, and it appears to be alright?

Any thoughts?

I had some very steep mountains routes in Stranda and I didn't use any pathways. I just called them climbs. If I used pathways I would probably not make them as steep, it looks silly with a bicycle in very steep terrain. I have no rules though, not my thing I frequently break them anyway.

The best way I've found is to test with a sim or vehicle. If the hill/path is so steep that the sim's feet sink into the ground an unacceptable amount, then you may wish to adjust it. If the hill is so steep that the car looks unnatural going up it, then you may wish to adjust the road. That's the test I use anyway.

No slope is too steep for sims or vehicles to go up and down on, so don't worry about routing in that regard. Believe me, I had some really hysterical experiences testing my world seeing sims climb up mountainous terrain because I hadn't laid down any non-routable paint. Sims have no problems climbing anything.

However, just know that if there's too much of a slant, it can just give some weird visual effects or come off looking very strange.

Too steep and it won't be accepted at mts