Once upon a time, Bill Harlan raced motorcycles, docked a schooner on seven continents and played professional poker. Now, he buys unwieldy swaths of Napa Valley wilderness.

Same sensation of thrill seeking, perhaps; different resource set.

Harlan rests in a singular sort of Napa Valley regency. With his fortune first built on the real estate firm Pacific Union, Harlan’s crown is now studded with the jewels of Harlan Estate and Bond wineries, and Meadowood resort with its three-star Michelin restaurant. At 76, he is about to officially unveil his latest — and presumably, last — wine estate, Promontory…