The 86th Floor
His office is on the 86th floor of a New York City skyscraper, implicitly the Empire State Building, reached by Doc's private high-speed elevator. Doc owns a fleet of cars, trucks, aircraft, and boats which he stores at a secret hangar on the Hudson River, under the name The Hidalgo Trading Company, which is linked to his office by a pneumatic-tube system nicknamed the "flea run." He sometimes retreats to his Fortress of Solitude in the Arctic — which pre-dates Superman's similar hideout of the same name. All of this is paid for with gold from a Central American mine given to him by the local descendants of the Mayans in the first Doc Savage story. (Doc and his assistants learned the little-known Mayan language of this people, allowing them to communicate privately when others might be listening.)
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