Where is the great Gloridax arena where the Grand Tournaments are held?

It's on Mount Mox

Not including Promo Edition cards, what card currently has the least in circulation?

At the time of this answer, Alpha Gold Foil Lightning Dragon

What is the name of the dark road that runs between Utopin and Galzur?

It's the Eternal Highway

For a picture, here you go! Missed a daily because of it... but totally worth it!