May 28

On May 28, 1892, naturalist John Muir spearheaded the founding of the Sierra Club with a mission to preserve the Sierra Nevada mountains. The organization quickly became a leading force in the early American conservation movement, advocating for the protection of wilderness areas and the creation of national parks. Through scientific research, legal action, and public outreach, the Sierra Club influenced landmark legislation protecting Yosemite and other iconic landscapes. Over the decades, it expanded its focus to include climate change, clean energy, and public lands management. Today, the Sierra Club remains one of the oldest and most influential grassroots environmental organizations in the United States, inspiring conservation efforts around the world.

On May 28, 1932, after 13 years of construction, the Dutch completed the Afsluitdijk, a 32-kilometer dam designed by engineer Cornelis Lely. By sealing off the Zuiderzee inlet, the structure converted the former saltwater bay into the freshwater IJsselmeer, reducing flood risks for North Holland and Friesland. The project enabled the creation of extensive polders for agriculture and improved water management in a country where much land lies below sea level. It stands as a landmark achievement in hydraulic engineering and Dutch ingenuity. Today, the Afsluitdijk remains vital infrastructure, combining transport routes with storm surge defense.