Started in 1865 as a warm mineral water resort with hunting, fishing, hiking, and horseback activities for guests, Gilroy Hot Springs was a very popular destination spot for movers-and-shakers with time and money. Imagine a 3-hour train ride from San Francisco to Gilroy, an overnight stay in town, then a 3-hour horse and buggy ride up 12 miles of dirt trails to reach the place. This isn't a quick day trip; most guests stayed one or two weeks, at least.

Many of the founding fathers of the Gilroy township had a financial interest in the Hot Springs. Newspaper articles, printed documents, and family photos show local business men and neighboring ranchers enjoyed time at the resort and business collaborations. The business and political associations nurtured by the astute and charismatic Gilroy Hot Springs owners George W. Roop and later William J. McDonald nurtured, contributed to the success and popularity of the resort. In the 1800s it was believed to have the most healing waters in California. These associations resulted in the railroad and Gilroy train station, redwood for the hotel, clubhouse, and cabins, and the Fleishhacker warm water pool.

The first outdoor warm-water Fleishhacker pool was installed in 1917 and attracted a new group of visitors. Roop, his son George B, or his granddaughter Florence continuously co-owned or held the mortgage from 1865 through 1938. Other notable owners during this time include Olden, Twombly, Cottle, Arrick, Tennent and Fitzgerald.

There were many political rallies, high brow dinner parties and music concerts, flag raisings, and holiday festivities. Gilroy Hot Springs was the destination spot for many decades. Roop and McDonald loved Gilroy Hot Springs, formed trusted relationships with influential leaders, and left a following of loyal family and friends.