Constructed during the creation of the artificial island of Maceno, this deep-sea geological research facility was used to monitor the formation of Maceno Reef. When the reef was completed, much of the site became unused. After the success of AG racing on the older and smaller artificial island of Arrivon, the newly established government of Maceno reached out to the AGL with an offer to turn the wide tunnels and massive domes of the underwater facility into a racing venue for their new group of Expert Tracks. The resulting track is commonly regarded as the most difficult the AGL has to offer, featuring multiple tight corner series and an infamous vertical drop hairpin. The long-term success of the Hydrome Bed circuit will determine whether Maceno Island will follow in the footsteps of Arrivon with more AGL entries - and so far the results seem promising.