us_capitol.jpegWASHINGTON (AP) – Congress is honoring the African-American slaves who helped build the U.S. Capitol.

Plaques have been erected inside the building in their memory.

The plaques read: “This original exterior wall was constructed between 1793 and 1800 of sandstone quarried by laborers, including enslaved African Americans who were an important part of the work force that built the United States Capitol.”

Historians have discovered that slaves worked 12-hour days, six days a week on the construction of the Capitol. The federal government rented the slaves from local slave owners at a rate of $5 per person per month. The slaves were not paid.

Congressman John Lewis of Georgia says that putting up the plaques helps tell the “full history” of the U.S. Capitol.