[2] The 11,700 square foot facility is home to 12,000 historical objects, the Sylvia Gaither Garrison Library and archives, permanent and temporary history and art exhibits, and performance space.

[6] The life and contributions of famous African American Maryland residents are highlighted in the permanent exhibition Deep Roots, Rising Waters: A Celebration of African Americans in Maryland, including Kunta Kinte, Benjamin Banneker, Frederick Douglass, Harriet Tubman, Matthew Henson, Carr's Beach, Gloria Richardson, and Thurgood Marshall.

The MCAAHC presented study results to the Governor suggesting the need for a permanent museum on Maryland’s African American heritage.

In 2005, a $5.2 million capital building and permanent exhibit expansion was completed at the museum adding a modern wing, which was the result of a partnership between the African American community and state and local governments.

[7] The library opened within the museum to collect and make available resources that document and elucidate Maryland's African American heritage.

In addition to her roles as Bates High School teacher, Fulbright Scholar, librarian, church leader, sorority sister, and community activist, Garrison was the central force behind the establishment of the Museum’s library.

The name change honors the legacy of Harriet Tubman, the iconic abolitionist, suffragist, and humanitarian, alongside Benjamin Banneker and Frederick Douglass.