Perched atop a mountaintop in Harriman, New York, Arden House rises like a fortress of ambition—100,000 square feet of all-American stone and steel. Built from 1905 to 1909 by railroad baron Edward Henry Harriman, this Gilded Age marvel was shared with the r/centuryhomes community in 2025. But it’s more than a grand house—it’s a defiant symbol of national pride, constructed entirely with American materials at a time when imitation of European palaces was the norm.

A Mountain Moved by Will

Harriman, the mastermind behind the Union Pacific Railroad, envisioned a home that embodied American greatness—no imported marble, no European trim. To build it, he reshaped a mountaintop 1,300 feet above the Ramapo Valley, blasting out a 50-acre plateau and carving 40 miles of trails across his 40,000-acre estate—larger than Manhattan.

Materials and workers ascended the site via a private cable railway. Under architect Grosvenor Atterbury, the house became one of the country’s largest, and American craftsmanship’s work ranged from stone to ceiling.

A Dream Cut Short, A Legacy Set Free

Tragically, Harriman lived just months in his dream home. In September 1909, at age 61, he died of stomach cancer, leaving behind a fortune worth $3 billion today. His widow, Mary, carried the torch, donating 10,000 acres and $1 million to establish Harriman State Park in 1910—a gift that continues to serve the public more than a century later. Their son, W. Averell Harriman, inherited Arden House in 1915 and went on to become governor of New York and U.S. ambassador.

A Home Reimagined

Arden House has lived many lives. During World War II, it became America’s first naval convalescent hospital. In 1950, the Harriman family donated the estate to Columbia University, transforming it into the nation’s first conference center.

World leaders like Nelson Mandela and U Thant once walked its halls. In 2011, ownership passed to a Chinese nonprofit, the Research Center on Natural Conservation, yet the house remains protected as a National Historic Landmark.

The Next Chapter Awaits

At 116 years old, Arden House stands poised for its next chapter. Preserved yet evolving, this 100,000-square-foot mountaintop estate is more than just stone and timber—it’s a symbol of vision, ambition, and legacy. Built by railroad titan E.H. Harriman with only American materials, it reflects a defiance of Gilded Age norms and a commitment to national pride.

As it awaits a new steward, Arden House quietly asks: who will carry its story into the next hundred years?