Quadriga

A quadriga is a vehicle, with one pole in the center, that is pulled by four horses (or other animals). Unlike modern carriages, the horses are all next to each other and none are in front of the others. The name is a contraction of quatuor ('four') and iugum ('joke'). Long ago, quadrigae were common in horse racing. Some chariots were also quadrigae.

A quadriga on top of Wellington Arch, in London.