I know of 2 speedways in this game.
First is the Bonzai Speedway in the dragon dojo level.
Second is the Rainbow Speedway, located right above you as you start Cloud 9
(you need 25 dragonflies to get there).
If you need more help, we've got more Spyro: Enter The Dragonfly cheats and also check out all of the answers for this game
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