did he also design it?
Yes, the society held a competition for designs, and he was the winner.
Washington Monument
The society held a competition for designs in 1836. In 1845, the winner was announced to be architect Robert Mill
who was president when the washington monument was built UNANSWERABLE when was it built? Construction began in 1848. when did it get completed? 1888 who built it? Robert Mills was the architect.
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Washington Monument [SEP] Design
Progress toward a memorial finally began in 1833. That year a large group of citizens formed the Washington National Monument Society. Three years later, in 1836, after they had raised $28,000 in donations (), they announced a competition for the design of the memorial. On September 23, 1835, the board of managers of the society described their expectations: The society held a competition for designs in 1836. In 1845, the winner was announced to be architect Robert Mills, supposedly the first native-born American to be professionally trained as an architect. The citizens of Baltimore had chosen him in 1814 to build one of the first monuments to George Washington originally planned for the former courthouse square in their port city, and he had designed a tall elaborately decorated Greek column with balconies, surmounted by a statue of the President.