The mission statement sounds a bit audacious: "We reveal stories about freedom's heroes, from the era of the Underground Railroad to contemporary times, challenging and inspiring everyone to take courageous steps for freedom today."

Boldness is needed when telling the story of a national disgrace, that of slavery.

The National Underground Railroad Freedom Center in Cincinnati, Ohio, tells that story. Opened in August 2004, this museum blends impressive multimedia projects, effective interactive modules, a range of stunning artifacts and plenty of stark history to make its points.

We picked up our audiophones and began our tour.

HUMAN CARGO

Architecturally, the complex makes a strong statement. Constructed of stone, rough-edged on the exterior, smoothly polished inside, the center sits close to the banks of the Ohio River, long the symbolic border between slave and free states in America. High ceilings, tall windows and a balcony overlooking the river also distinguish the building.

Glorious architecture pales beside the story of slavery, made immediately vivid by the presence of an 1830 slave pen moved from its original location in Maysville, Ky.

In places like these, human cargo was warehoused en route to auctions and sales. Of solid wood construction, the pen gives off the solidity of a fort. Inside, its hand-hewn log interior looks quite handsome -- until you remember it enclosed a holding area for slaves.

SELLING PEOPLE

The large third-floor gallery, "From Slavery to Freedom," provides a vivid history of slavery in North America. Captured in Africa, slaves traveled by ship to Caribbean islands, from where they were sent to Spanish, French and American colonies in the New World.

Miserable conditions aboard crowded ships were gradually improved, not for humane reasons but to preserve profits. Excessive mortality rates during voyages simply left fewer humans to sell at market.

After all, slavery was a business (and a profitable one) -- that of selling people.

Sugar was the crop that initially brought slaves to North America. Later, tobacco, coffee and rice plantations bought labor. But it was the explosion of cotton that incited the greatest exploitation. By 1830, the value of cotton exceeded that of all other products in the United States combined.

BREAKING UP FAMILIES

Exhibits are careful to point out that not only southern plantation owners profited from slavery. The growth of northern industry and the development of railroad networks depended on the success of a cotton economy, too. And slave trading took place in New York City and Rhode Island, not just in Richmond and Charleston.