Trike Flock
The Trisled was my first trike, and one of the best.  I wish I still had it.  This rare Australian trike was one of the few special ordered for import to the United States.
The thin steel frame allowed it to be both strong and light.  Rim brakes indicate its early vintage.
With its low and narrow profile and tight steering geometry, it was very fast and handled like a sports car. 
Those characteristics made the Trisled ideal for high speed mountain descents.