auditory conjuration sonic 

Traditions occult

Cast [>>] somatic, verbal

Area 30-foot line

Duration sustained

By playing a brief tune on an instrument or in song, you cause the notes of the melody to physically manifest into a shimmering, translucent path. This path doesn't need to be over solid ground and can tilt up or down diagonally up to 45 degrees, but it must be a straight, 5-foot-wide line.

It can support as many creatures as can physically fit on the bridge.

Secrets of Magic, page 129.