I have searched all over this level and have found as much as I can. I’m still missing a lot of treasure and a missing dragon. I can see around the back of the main tower, there is a platform with some mushrooms jumping around. I have tried to get over but I can never get enough height to glide over. I have searched all around for any secret entrance but no luck. I see a square hole in the roof to get to the treasure but I have no way to get up there. How do you reach the hidden treasure in Haunted Towers in Spyro?
Figured it out. The area around the back is where you have to land. You need to use the speed boost to pull off a very specific run in order to generate enough speed to make the flight. I have made a video showing how to get to the secret area in Haunted Towers. All of the missing gems were over here.