A sign marks the intersection of the Canon Brook Trail and the South Ridge Trail on Cadillac Mountain in Acadia National Park. Aislinn Sarnacki | BDN

When Sieur De Monts National Monument was founded on Mount Desert Island 100 years ago, its creators sought to protect the island’s stunning natural resources from development and to preserve them for public access. Now, with the rise of state’s tourism industry over the past several decades, the economic impact the federally conserved land now known as Acadia National Park has on the surrounding area and on the state as a whole can be included among its major influences. Where once a handful of philanthropists saw mountains, lakes and rocky ocean beaches, now scores of tourist-related businesses also see hundreds of millions of dollars in revenues each year. Here’s a look back at key events in Acadia National Park’s history.

1901

Hancock County Trustees of Public Reservations is formed by wealthy seasonal residents on Mount Desert Island to preserve the island’s pristine scenery and to maintain public access to it. The growing use of automobiles and portable sawmills inspire their conservation efforts.

1916

President Woodrow Wilson authorizes the establishment of Sieur de Monts National Monument on Mount Desert Island with 6,000 acres of land donated by the Hancock County Trustees of Public Reservations.

1919

Congress votes to change Sieur de Monts National Monument to Lafayette National Park.

1929

The name of Lafayette National Park is changed to Acadia National Park.

The estate of John G. Moore donates 2,000 acres of land at Schoodic Point to the park.

1942-1945

After getting hundreds of thousands of visits each year, visitation to Acadia plummets during World War II.

In 1943, the heirs of Ernest Bowditch convey 2,700 acres on the Knox County island of Isle Au Haut to Acadia.

1947

A devastating forest fire (one of several in Maine that year) sweeps across 17,000 acres on eastern Mount Desert Island. The fire destroys dozens of summer cottages, compounding the economic losses many seasonal rusticators experienced during The Great Depression and World War II. Many wealthy families leave and never return.

1949

St. Croix Island, where French colonists attempted to establish a settlement in 1604, becomes a national monument and is managed by Acadia. Located in the St. Croix River between Maine and New Brunswick, it becomes a shared international historic site with Canada in 1984.

1960

Annual visitation levels to Acadia leap over the 1 million mark for the first time and stay there, going from an estimate of 755,900 in 1959 to more than 1.6 million the following year. Park officials won’t speculate about the cause of the sudden increase, but it coincides with the national expansion of the Interstate highway system in the 1950s and 1960s and, more specifically in Maine, with the northward extension of I-95 from Augusta to Fairfield in 1960.

1966

Official Acadia visitation estimates permanently pass 2 million a year.

1990

Hoping to get more accurate figures, the National Park Service changes its methodology for estimating the number of annual visits to Acadia, resulting in a change from 5.4 million visits in 1989 to 2.3 million visits the following year. Despite the change in methodology, the trend in year-to-year fluctuations since 1960 generally remains in range of 30,000 to 300,000 visits.

1990s & 2000s

The number of hotel rooms in Bar Harbor increases as five new large hotels are built. During the same time period, the number of yearly cruise ship visits to Bar Harbor increases from 22 in 1990 to a state record of 127 in 2014.

2002

The Navy transfers a 100-acre former military facility at the tip of Schoodic Point to Acadia, which converts the facility into the nonprofit Schoodic Education and Research Center.

2015

An anonymous donor gives 1,441 acres on the Schoodic Peninsula to the park.

The park’s annual visitation estimate increases to 2.81 million visits, the highest yearly calculation since 1995, when it had 2.84 million visits.