Intermediate circuit: 

Finish in first, second or third place on 
the beginner circuit to unlock the Mission
track and the intermediate circuit.


Extreme circuit: 

Finish in first, second or third place on 
the intermediate circuit to unlock the 
Presidio track and the extreme circuit.


Advanced circuit: 

Finish in first, second or third place on 
the extreme circuit to unlock the Gauntlet
track and the advanced circuit.