The discovery of a world-wide undersea mountain range that has a deep fissure down its center has suggested to some geologists that the earth may be slowly expanding rather than contracting ...

A good mountain bike for under $2,500 seems almost impossible these days, but there are still options out there for riders ...

A single mid-ocean ridge system connects the world's oceans, making the ridge the longest mountain range in the world. On land, giant troughs such as the Great Rift Valley in Africa form where ...