
You need a mushroom or a star to do this (it is much harder if you use a star). You can take a big shortcut if you jump across the river just after the first big turn.After the first shortcut you can jump back over the wall and land before the finish line, this is very hard to do, but possible.When you first start the race, you can jump the wall at the top of the hills, you can save almost half a lap this way.Just before you enter the tunnel use your star, if you do this right you'll finish the lap and have a shorter 2nd or 3rd lap. When you get to the 2nd Railroad tracks turn and go to the tunnel. On the first or second lap if you get a star you can do this.

A mushroom, star, or a last second power slide helps

That road will take you to the Mario 64 castle.

Follow the yellow road in Royal Raceway, just after the big jump and to the right.
