A gargoyle is a stone carving, usually of a strange or frightening creature, that sticks out from the side of a building. Originally, gargoyles served a practical purpose: they were waterspouts that directed rainwater away from the walls of medieval churches and cathedrals. The water would flow through a channel in the stone creature and pour out of its mouth, protecting the building from water damage.

Medieval stoneworkers carved gargoyles into wild and imaginative shapes: dragons, demons, lions, wolves, and bizarre combinations of different animals. Some had wings, horns, or fangs. Others looked like twisted human faces frozen in strange expressions. Walk around an old European cathedral and you might spot these creatures perched high above, seeming to watch over the streets below.

Today, architects sometimes add gargoyle-like decorations to buildings just for their dramatic appearance, even when they don't actually carry water. These purely decorative carvings are technically called grotesques, though most people just call them gargoyles anyway.