Even some small calliopes are audible for miles. Peru is also the home of the world's only remaining manufacturer of steam calliopes. These calliopes are featured in Peru's annual Circus City Parade. The name is possibly referencing the mechanical complexity of calliopes. Their calliopes are played regularly on river excursions. Some calliopes can also be played via a MIDI interface. Calliopes usually have very loud and clean sound. Only a few calliopes have survived, and these are rarely played. Calliopes can be played by a player at a keyboard or mechanically. Starting in the 1900s, calliopes began using music rolls instead of a live musician. Calliopes are used as outdoors instruments, and many have been built on wheeled platforms.