* Collision: When two continental plates collide, they are both made of relatively light, less dense rock. Neither plate can subduct (slide) under the other.

* Folding and Uplift: Instead of subduction, the intense pressure from the collision causes the rock to buckle, fold, and uplift, forming massive mountain ranges.

* Examples: The Himalayas, formed by the collision of the Indian and Eurasian plates, are a prime example. The Alps, the Andes, and the Appalachian Mountains were also formed through continental-continental collisions.

Let me know if you'd like more details about specific landforms or the geological processes involved!