The entrance to today’s Ship Canal was once the outlet of a small stream that flowed from Lake Union to Puget Sound. The creek was dredged and channelized with the creation of the Lake Washington Ship Canal, providing passage between Lake Union, Lake Washington, and the Puget Sound via the Chittenden Locks. On July 4, 1854 Seattle’s leaders gathered at Thomas Mercer’s house overlooking the lake. On that day they gave a new name to the lake that for thousands of years was known as ha-ah-chu. They chose the name Lake Union because they believed it would become the union between Puget Sound and Lake Washington. Without any tools aside from shovels and axes or any technical knowledge, they predicted the creation of the locks that, nearly 65 years later, radically changed the nature and economy of Lake Union.