Three teams of architects worked on the design of the Capitol during the 32 years of its construction, managed by: Thomas Fuller (1867–1875), Leopold Eidlitz and Henry Hobson Richardson (1875–1883), and Isaac G. Perry (1883–1899).

[6] The legislative chambers, the fourth floor and roof work were all finished in Victorian-modified Romanesque that was distinctively Richardson's design.

The granite structure is 220 feet (67 m) tall at its highest point, and it is one of eleven U.S. state capitols that does not have a domed roof.

[8][9] A previously covered skylight over the Great Western Staircase was uncovered and restored to functionality, and the Ludowici tile on the roof was replaced with new material from the original producer.

[11] The Capitol initially featured two large murals by Boston artist William Morris Hunt painted directly on to the Assembly Chamber's sandstone walls.

Plans for later murals by Hunt were abandoned due to lack of funding, and some people have speculated the resulting depression experienced by the artist may have contributed to his suicide.

In front of the Capitol is an equestrian sculpture of Civil War General Philip Sheridan, designed by John Quincy Adams Ward and Daniel Chester French and completed in 1916.

The flames reached 200 feet (61 m) at one point, requiring the evacuation of nearby homes; the fire took 125 firefighters to extinguish.

[16] Heat from the fire was intense enough to twist framing in a skylight above the building's western stairs and melt their sandstone filigree.

Official guided tours of the Capitol are offered at various times beginning at the Information Desk located in the State Street Lobby.