Back جبل متطوي Arabic Qırışıqlı dağlar Azerbaijani ভঙ্গিল পর্বত Bengali/Bangla Foldebjerg Danish Faltengebirge German Faldmontaro Esperanto Kurdmäestik Estonian کوههای چینخورده Persian Poimuvuoristo Finnish Fillsléibhte Irish
Fold mountains are formed by the effects of folding on layers within the upper part of the Earth's crust. Before the development of the theory of plate tectonics and before the internal architecture of thrust belts became well understood, the term was used to describe most mountain belts but has otherwise fallen out of use.