Plugs

Gotta love the internet! A popular tourist destination in Camaroon is Rhumsiki--home of the "volcanic plugs". I had no idea such a thing as a volcanic plug existed--but the internet and google images knows all about them.

Here's what Wikipedia has to say:

A volcanic plug, also called a volcanic neck or lava neck, is a volcanic landform created when magma hardens within a vent on an active volcano. When forming, a plug can cause an extreme build-up of pressure if volatile-charged magma is trapped beneath it, and this can sometimes lead to an explosive eruption. If a plug is preserved, erosion may remove the surrounding rock while the erosion-resistant plug remains, producing a distinctive upstanding landform.
Very cool. I like the mental image of a plug for a volcano like a plug in a bathtub, even if that image is completely inaccurate.