VERY unique tour with the underground halls and above-ground atriums. Numerous art displays, and excellent quick-history backstory on new, landmark, and previous no longer existing buildings, along with existing 18th and 19th century hold-outs, former mansions of the past. Our guide, Rob, was knowledgeable and amiable. He was conscientious about the pace of the walking and restroom breaks--this isn't his first rodeo! His research was much appreciated. Bravo.