http://www.newsweek.com/scientists-discover-supermountains-stretched-4000-miles-1676728

Prehistoric "supermountains" that stretched around 4,500 miles and dwarfed the modern-day Himalayas has been discovered by scientists.

Their research, published in the journal Earth and Planetary Science Letters, reveals a previously unknown mountain range named the Nuna Supermountains, which existed on a vast ancient continent between two and 1.8 billion years ago. They also describe a second vast mountain range, which arose between 650 and 500 million years ago and is named the Transgondwanan Supermountain.