Washington Monument
This landmark is the Washington Monument in Washington DC. As of 2022, it is the world’s tallest obelisk. It is 554 feet 7+11⁄32 inches (169.046 meters). The monument commemorates George Washington, the United States’ first president. Architect Robert Mill designed the memorial with construction beginning in 1848. Workers finished the obelisk in 1884. Marble, granite, and bluestone gneiss are the materials that make up the structure.