Which horn is used in marching bands - Other the French Horn?

French horns are not used in Marching Bands. They are too unstable to march with effectively.

Bands that march french horns are insane.

The marching version of the french horn is called the "mellophone".

There is also an instrument similar to the mellophone named the "marching french horn", but they are essentially the same instrument with a different mouthpiece.

Additional marching brass instruments are trumpets, trombones, baritones, and tubas