VIENNA (AP) — It's the day that Marty McFly landed in the future — and Austria's transport ministry is ready with guidelines for hoverboards.

Fans of "Back to the Future 2" know that McFly arrived on Oct. 21, 2015 — Wednesday. They also will remember the hoverboard sequence, with McFly being chased by Biff and his gang, all on flying skateboards.

These may never go beyond the prototype stage. But the ministry has issued tongue-in-cheek rules on their use to mark "Back to the Future" day. Its website describes a hoverboard as a "small vehicle for use outside of the road" and says a special license is needed for rocket-driven "Pit Bull" models.

It urges hoverboarders to wear helmets and to "be aware ... of possible additional regulations" for use over water.