Founded by John D. Rockefeller Jr. in 1951, Historic Hudson Valley (www.hudsonvalley.org) operates visitor programs at Westchester County treasures such as the pre-1750 Van Cortland Manor. Renowned for its annual Great Jack O’ Lantern Blaze—where on autumnal weekends, visitors stroll through a nighttime fantasy of some 5,000 carved and illuminated pumpkins—this historic site introduced a new program in May called Lightscapes.

Featuring recyclables and other materials magically transformed into giant mushrooms, insects and other sculptures animated by light, sound and special effects, this “springtime garden fantasy” vividly illustrates inventive possibilities for groups across accessible, product-rich Westchester County.

“Historic venues such as the Rockefeller estate at Kykuit [conferencing available for select groups] are typically limited to small groups on guided tours,” says Rob Schweitzer, public relations director for Historic Hudson Valley. “Events like Lightscapes are keyed to accommodating larger audiences with reimagined content and experiences.”

Available for groups on non-public nights this year, the Blaze features a 5,000-square-foot hospitality tent.

Fantasy also comes alive at the 31-room Castle Hotel & Spa in Tarrytown. Set on 11 hilltop acres, this national landmark features the award-winning Equus Restaurant, regal group spaces and unique in the U.S., the new $12 million THANN Sanctuary Spa. Complete property buyouts are available, with helicopter service from Manhattan to Westchester County airport an elite new feature.

Meanwhile, Renaissance Westchester in West Harrison recently completed a renovation of its guest rooms, lobby and restaurant. The property has over 20,000 square feet of meeting space.

Offering 10,000 square feet of group space, the 146-room (38 suites included) Ritz-Carlton, Westchester, housed in a glass skyscraper with top-floor dining space, is a group magnet on aptly named Renaissance Square in revitalized White Plains.

“Forward-thinking capital improvements maintain Westchester County’s appeal as a smart destination for business,” says Natasha Caputo, director of Westchester County Tourism and Film. “White Plains exemplifies the county’s continued reinvention with its quality meeting spaces, great restaurants and dynamic events.”