Walter Graeme Ladd and his wife, Catherine (“Kate”) Everit Macy Ladd, began to acquire small local farmsteads in what are now Peapack-Gladstone, Far Hills and Bedminster in April 1905. Eventually, the Ladd’s created one of the largest estates in the area, encompassing 1,000 acres stretching from what is now Route 206 on the west, across the North Branch of the Raritan River on the east, and from Highland Avenue in Peapack on the north, to what is now Route 202 on the south. They named their estate “Natirar,” an anagram for the Raritan River that meanders for two miles across the property. The 33,000 square-foot Ladd residence was completed in 1912 by the prominent Boston architect, Guy Lowell, who is famous for his design of the Boston Museum of Fine Arts and New York County Courthouse on Foley Square in Manhattan, and Henry J. Hardenberg who is best known for designing Copley Plaza in Boston and the Plaza Hotel in New York City.
Beginning in 1908, Mrs. Ladd had provided a convalescent facility for women on the Natirar estate, originally at “Maple Cottage,” a large residence that once stood along Peapack Road. Her husband established a fund to ensure the work's continuation, and following Mrs. Ladd’s death, title to Natirar was conveyed to the Kate Macy Ladd Fund and The Kate Macy Ladd Convalescent Home was relocated from “Maple Cottage” to the renovated main residence, where it operated until 1983. In May of 1983, 50 years after Walter Ladd’s death, The Kate Macy Ladd Fund sold the property for $8.5 million to King Hassan II of Morocco, in accordance with the provisions of Mr. Ladd’s will. King Hassan died in 1999 and Natirar was inherited by his son, Mohammed VI.