Luigi Circuit is a track that appears in a lot of Mario Kart games, the well known one is from http://www.mariowiki.com/Mario_Kart_Wii (Mario Kart Wii). Here is it's latest appearances for other consoles.
Mario Kart DRAX
Mario Kart DRAX is a game for the Wii U and has Luigi Circuit on the game in the Flower Cup. The course is named easy because of the base of the track and how it is set out. There are three laps, laps are also based on how long the course is in the game. to see more about that game click the link above in blue writing. (PLEASE NOTE: If you have a Luigi Circuit on your Mario Kart edit, why not put it on here? I have loads more space for the edit so why not. After reading this message you can remove it.)