Who was the architect responsible for designing the 1855 dome?

The architect responsible for designing the 1855 dome of the United States Capitol is Thomas U. Walter. His work on the Capitol dome was part of a larger expansion project that aimed to accommodate the growing functions of the government. Walter's design included the iconic cast-iron dome that we see today, which is both a structural and aesthetic centerpiece of the Capitol building.

He implemented a neoclassical architectural style that complemented the original design while enhancing the building's overall grandeur. The dome was completed with a distinctive lantern atop it, further solidifying its place in American architectural history. Thomas U. Walter's contributions significantly impacted the shape and appearance of the Capitol, making it one of the most recognizable landmarks in the United States.