How to properly distinguish a transversal valley from a longitudinal valley?

Question

I'm confused about how to distinguish the two. Prior to making this question. I've read the wikipedia entry on the subject but it mentions that for example a transverse valley makes 90 degrees with that of the main mountain chain.

I'm not savvy with terrain profiles, so this clue about angles makes me confused. So could someone help me with an adequate diagram or picture on how to distinguish it from a longitudinal valley?

The same entry mentions about Val de Travers which it warns that despite of its name is a longitudinal valley. But I don't know why does it make this claim.

Because none of the articles do properly explain this with some sort of picture other than a photo I can't exactly tell at which difference is being talked about. Thus an arrow or some sort of marker or indicator over the photo or a diagram would be of much help for better identification.

Answer 1

I think that the simplest way is to just look at the map for these two valleys in the Switzerland:

Longitudinal valley:

You can see that this is perfect example on the map: we can easily see the direction of the ridges and the valley is pointed in the same direction. This type of valley was not made by river, but it was made with compressing of tectonic plates.

Transversal valley:

You can see here that some river got through the ridge (then they built the road because the river made all work). It doesn't go parallel ridges like the longitudinal valley. This type of valley requires a lot of work for the river so transversal valley are typically pretty short.