After taking another look at this image of the Master Bike, I noticed there's actually a bit of a backround drawn in there aswell, being Hyrule Castle, specifically the one from Twilight Princess, off in the distance, meaning Link here is driving in Hyrule Field. Could this mean that's where the Zelda track will take place? Originally I thought it'd be Skyloft since Link is in his Skyward Sword design as seen here:
Woulda made sense with you being able to glide everywhere, but I feel that would be redundant with Skyloft already appearing in SSB4. But thankfully in addition to Hyrule Field in the artwork, we also have a Hylian Shield on the Master Bike, and the Master Bike itself is shaped like a Horse, neither of which were in Skyward Sword, both of which were in Twilight Princess. Afterall a Horse has always been the best way to traverse Hyrule Field, so it makes perfect sense to have the track be Hyrule Field with a Horse-like vehicle. If the track was going to be Skyloft, I'm sure they woulda made the vehicle after a loftwing. Plus this isn't Skyward Sword DLC, it's Zelda in general DLC, and Hyrule field is way more iconic than anything in Skyward Sword. So with all that said, I'm confident that this is where'll be racing soon! 
