Brazil's hidden slavery past uncovered at Valongo Wharf

Rio de Janeiro is a city looking to the future. Major development work is underway in the city's historic port area as it prepares to host the Olympics in 2016.

But the construction effort to make all that happen has unexpectedly shone a light on a dark side of Rio: its past as the largest entry point for African slaves in the Americas.

In 2011, excavation work uncovered the site of Valongo Wharf, where almost a million African slaves disembarked before the slave trade was declared illegal in Brazil in 1831.

The wharf and the complex surrounding it were constructed in 1779 as part of an effort to move what was regarded as an unsightly trade to an area far from the city centre.

Apart from the piers, the slave market also had forges where chains and shackles were sold and numerous shops where the slaves were displayed for sale.

A few blocks from the wharf is a cemetery where, between 1770 and 1830, thousands of slaves were buried. Many slaves, weak after the long crossing, died soon after arriving in Brazil.

The cemetery's exact location was only uncovered in the 1990s, when a couple renovating a house discovered a large number of bones.

The area is a stark reminder of the role Brazil played in the slave trade.

More than four million slaves were taken to Brazil over three centuries. That is 40% of all slaves brought to the Americas.

And despite the official abolition of the slave trade in 1831, the clandestine trade continued to flourish.

Slavery itself, rather than the trade in slaves, was not banned until 1888, making Brazil the last country in the western world to abolish the practice.

A few blocks from the site of the wharf, ambitious plans to tell this story to visitors from all over Brazil and around the world are taking shape.

In an old coffee warehouse, city officials are creating a centre for urban archaeology where items found during the regeneration of the area will be displayed.

Among them are many objects of African origin such as ornaments, pipes and religious artefacts, as well as pieces of china, silverware, wooden dice and toothbrushes.

The president of Rio's World Heritage Institute, Washington Fajardo, says the centre, which he calls an "open lab", will officially open for visitors by late 2015.

He says that, rather than a museum, this will be a place to watch archaeologists at work and connect with history.

"We want people to see the objects and witness the archaeological process so they can have a concrete understanding of what the port was and what happened here," he says.

Two new signs mark the Valongo Wharf as a stop on Rio's African Heritage route, as well as Unesco's International Slave Route, a project which aims to preserve the heritage related to slavery.

Historian Claudio Honorato guides university students around the site.

He recalls how until recently, it was buried underneath a square, a street and a parking lot.

Mr Honorato, who wrote his Master's thesis on the Valongo Wharf, even remembers parking his car on top of this historic site.

He says its preservation is of key importance.

"This whole area was a major slave market and all the sites associated to that trade have disappeared. The Valongo Wharf is the only one remaining," he explains.

Anthropologist Milton Guran, who co-ordinates the bid to have Valongo recognised as a Unesco World Heritage site, thinks preservation is especially important because "we had successive attempts to erase this history".

"Slavery finally started being perceived as something heinous and the Empire sought to obliterate that mark," he says.

In 1843, the wharf was refurbished for the arrival in Brazil of the Italian Princess Teresa Cristina Maria de Bourbon for her wedding to Brazil's Emperor Dom Pedro II.

It was renamed Empress Wharf in her honour.

After Brazil was declared a republic in 1889, the site was used as a landfill and eventually a square was built over the wharf.

The only thing that reminded passers-by of its long history was a column marking the location of the Empress Wharf.

But there was no mention of its links to slavery and Valongo pier.

Mr Guran says this is not surprising as there has long been an attempt to dilute the importance of Brazil's African population in building the country and its identity.

The impact of slavery on Brazilian society can be seen to this day. Over half of Brazil's population is black or mixed race, but its elite remains largely white.

But Mr Guran says there is a "growing awareness of how we are determined by our African roots".

"And this is symbolically represented by the unveiling of the Valongo Wharf."