Significant events of the past half-century or so in the town of Henderson include:

December 1946: The federal government declares that the 868-acre rifle range on Stony Point is surplus property and is to be sold. That declaration "completes the cycle whereby the once heavily used Army installations bordering Lake Ontario are wiped off the War Department's training chart," the Watertown Daily Times reported then. The range was established in the 1880s by the Army for use by infantry troops from Madison Barracks in Sackets Harbor and Fort Ontario in Oswego. Firing was aimed over the lake. Utilization of the range for anti-aircraft firing practice was established in 1925, and the "pill boxes" from those exercises are still visible on the shore. From 1942 to 1944, the government had spent $350,000 building a 3.6-mile concrete road to the range from Aspinwall Corners.

June 1950: Westcott Beach State Park on the town's northern edge is dedicated and opened. Gov. Thomas E. Dewey attended and said the opening was a significant step in the development of state parks in the state's north region. The state had bought the land, including 170 acres on both sides of Route 3 and 2,600 feet of lakefront, in 1949 for $30,000 from the Westcott family.

1958: The Air Force spends an estimated $1 million constructing a communications center off Lighthouse Road on Stony Point. From Aug. 3, 1959, until May 13, 1960, the site was used as a test annex to develop new forms of low-energy, high-speed communications. Tests were run 24 hours a day. Researchers used six radio towers to send and receive messages with two forms of experimental communication technology between Stony Point and Carrabelle, Fla. The tests led to advancements in "over the horizon radar"(bouncing radar signals off the ionosphere to extend the radar range ) and to the development of tropospheric communications.

Summer 1956: General Electric holds the last of its "encampments" on Association Island. The island had been bought, and named, in 1906 by the National Electric Lamp Association as a summer camp for business discussion and inspiration for male employees. As one of the founders said, "If men can relax together and enjoy each other's company, they can work together efficiently and profitably." Family members were invited for the second half of the summer in 1911, and the company was bought by GE the following year. By 1950, the popularity of the island experience meant that only 3,000 could be accommodated at the annual encampment, although many more were eligible to attend. By 1956, GE had expanded its executive training and inspirational program by setting up courses at every plant and had established a full-time Management Research and Development Institute in Crotonville, Westchester County.

Sept. 15, 1959: General Electric donates Association Island and adjacent Showshoe Island to the New York State Young Men's Christian Association to use as a summer camp. But the wide distribution of YMCA branches statewide, some of which were supporting their own summer camps, made it difficult for many branches to send groups to the island. In 1967, the YMCA decided that running the camp was too great a financial strain. Two years later, Association Island Recreation Corp. was formed to continue public use of the islands for conferences, environmental studies and recreational activities, such as hosting the Syracuse Symphony Orchestra, and music and drama workshops. The corporation bought the islands in 1972 for $125,000. The islands were also the headquarters for trial yachting races for the summer Olympics in 1976.

1963: Rochester Portland Cement Co., a subsidiary of Lake Ontario Portland Cement Co., proposes to build an $11 million cement plant in Henderson that would employ 200 people and produces 1,500,000 barrels per year. The firm originally proposes the plant on 20 acres near White's Bay, but opposition to that sight pushes it to seek land out on Stony Point. It eventually buys 215 acres there and obtains options to buy hundreds more acres. Construction, put off several times, was eventually scrapped entirely in 1973 because the company's major source of sand, in Picton, Ontario, is taken by the Ontario government for use as a park. Opposition to the original sight spurs the formation of a "protective" association, which would become the Henderson Taxpayers Association.

1966: Phillips Petroleum, based in Bartlesville, Okla., acquires the Stony Island holdings of Sealright Corp. when it buys that company. Oswego Falls-Sealright Co. of Fulton had bought 640 acres on the island and the island's famous limestone lodge from the Alexander Cowie family in 1949. Phillips begins using the property as a corporate retreat on a regular basis in the mid-1970s. Though the island is wholly within the town of Hounsfield, Phillips maintains a large boathouse along Harbor Road in Henderson Harbor. The company employs about 18 people and buys many of its supplies through Henderson businesses. Low oil prices prompted Phillips to curtail operations on the island three times since 1980 the most recent in 1999 for about a year each time.

July 1984: The Belleville and Henderson central school districts merge, resulting in the subsequent closing of the Henderson school.

June 1990: Robert G. Wehle, member of the family that produced Genesee beer, sells 1,066 acres of land on Stony Point to the state Department of Environmental Conservation for $2.7 million. Mr. Wehle was granted lifetime use as part of the agreement, and he continued to pay property taxes on the land. Mr. Wehle died July 12, 2002, at age 82. The property is eventually to become a state park.

1996: The former Henderson school reopens as apartments for senior citizens after a $2 million renovation by Christopher Communities of Syracuse.

Spring 1996: The Henderson Historical Society opens its museum and genealogy research center in the former Universalist Church, built in 1839. The church was turned over the society in 1995 because of dwindling church membership.

Jan. 7-8, 1998: A massive ice storm knocks out electricity and downs trees throughout Northern New York and southeastern Canada. Power is out for four to five days in most places in Henderson, and for as long as three weeks for some others far removed from the center of town. A shelter is set up in the fire hall.

July 27, 1998: More than 850 federally protected double-crested cormorants are killed by gunfire on Little Galloo Island. For at least a decade, the cormorant population on the island had been exploding, and spreading to Gull and Bass islands, and the birds were blamed for the decline in the local sports fishery, especially smallmouth bass and perch. Ten Henderson Harbor-area men pleaded guilty in U.S. District Court in Syracuse on April 8, 1999, in connection with the killings and were fined and/or sentenced to home confinement. The publicity from the slaughter prompts the U.S. Fish and Wildlife Service to allow the state Department of Environmental Conservation to begin oiling the eggs of cormorants. Oiling to suffocate the chick embryos inside, instead of breaking eggs, discourages cormorants from nesting at other locations and from laying more eggs.

2000: The federal census counts 1,377 Henderson residents, with a median age of 44.4, second-highest median age among all towns in Jefferson, St. Lawrence and Lewis counties. (In the summer, the population swells to about 10,000.)

May 3, 2002: Groundbreaking is held at the Charter House in Henderson Harbor for the $4.1 project to bring municipal water service to the hamlets of Henderson and Henderson Harbor. Water is expected to flow sometime in the fall.

May 2002: The Association Island campground for recreational vehicles opens for Memorial Day weekend. Island owner Dr. Nak K. Shim, a retired orthopedic surgeon, had been creating the 300-site recreational-vehicle park and marina on the 100-acre island since the Town Council, on March 12, 1999, approved a zoning change for the island from island district to planned development district. He and other investors bought Association and Snowshoe islands in 1981 with the intention of building townhouses. He later bought out his partners. Controversy over the RV proposal had existed since he proposed it in late 1991 and was punctuated by many delays, lawsuits by Dr. Shim and the opposing Henderson Taxpayers Association, legal appeals, and the trial and acquittal of Dr. Shim on a bribery charge.