In the second province, near the Kusong Mash, there is a big bridge. If you are in a helicopter, you can destroy it. Once the smoke is gone you can see that it is now a jump. Land the helicopter and call for a civilian street racer. Back it up and burn out for extra speed. Go all the way and launch off the bridge. Note: While shooting at the bridge you may lose money or faction points for blowing up a civilian car.