It will rise 12-stories and feature a 90-degree hill, "The Joker," Six Flags Great America's newest roller coaster in Gurnee is almost done.

The free-fly coaster and it's almost done. The last piece of the track was installed today. We hope the construction workers are not afraid of heights.

You'll have to wait until Memorial Day weekend to give 'The Joker' a spin, but before you jump aboard, we thought you might like to see how it was constructed.

Now that you know how it was constructed, here's what you'll experience once you get on board.