World's largest tyrannosaurus kidney stone found at CCDC. Fun fact. When building this structure in 1984, the rock that is seen in the front of the lobby was originally mounted and displayed approximately 70 feet North. This was to symbolize that all stones can't be removed. This T-Rex kidney stone was polished and rubbed for good luck. This is a great starting point for those who are getting married or taking in the sights and sounds of the Las Vegas downtown area.