The seven-and-a-half-acre memorial sprawls along 800 feet of the Tidal Basin's southwestern shore, adjacent to the Jefferson Memorial.

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The tidal basin formed by the two converging rivers was named "dubh linn" (meaning "black pool") by Celts, who had inhabited the area upstream as early as 500 BC.

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The US Congress authorised the memorial in 1996, and groundbreaking is scheduled for late next year on a four-acre site among trees on the National Mall, beside Washington's Tidal Basin.

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Guided tours with National Park Rangers, pet-friendly walks, food tents, live stage performances and even a ranger-led bike tour and night walk around the Tidal Basin will be part of the free activities at the National Mall.

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