By Alexis Akwagyiram
BBC News, in Elmina, Ghana
The castle was built by Portuguese traders in the 1400s
Amid the backdrop of crashing waves and palm trees, about 500 people assembled in the courtyard of the former slave fort to remember those who passed through that door and others like it across Africa.
Elmina Castle was the first European slave-trading post in sub-Saharan Africa.
On Sunday evening, hundreds of locals watched on a giant screen the castle as politicians, poets and musicians attempted to make sense of the past.
The hypnotic rhythms of traditional African drumming filled the tropical afternoon air to signal the start of the ceremony.
Clad in colourful cloths, a troupe of musicians played and chanted traditional songs to mark the arrival of a local chief and later the guests of honour - Ghana's president John Kufuor and UK representative Baroness Amos, leader of the House of Lords.
The British Council had organised a commemorative event at the former slave fort to mark the 200th anniversary of the Abolition of Slave Trade Act in the UK.
Nobody knows exactly how many Africans went through the Door of No Return.
But every slave leaving Elmina Castle to be forcibly transported overseas emerged from a dark dungeon through that narrow hatch.
Traditional drumming marked the start of the ceremony
Ahead of the event, one of the organisers, Akunu Dake, outlined the ethos underlying the ceremony.
"This event is not a concert. It is an opportunity for us to come together as artists to explore avenues and express ourselves in our many forms - that is the flourishing of the human spirit," he told reporters.
Similarly, Amanda Griffiths, deputy director of the British Council in Ghana, said: "This marks a very spiritual day, particularly for people who have grown up within the African Diaspora.
"They especially feel the pain that their ancestors went through and know they went through the door at Elmina or ones like that."
The council's director, Moses Anibaba, said: "The commemoration involves laying foundations and building a new order of human relationships in which the continent of Africa takes its rightful place on the world stage."
At the event, both President Kufuor and Baroness Amos gave stirring speeches in which they offered personal views of the slave trade and the effect it had on Africa and the descendents of those wrenched from the continent.
Baroness Amos, who expressed pride at being a member of the African Diaspora, said transatlantic slave trade had been "responsible for some of the most appalling crimes perpetrated by humankind against its own citizens".
She went on to describe it as "one of the darkest and most uncomfortable chapters in British history" before calling for future generations to learn from mistakes of the past in order for them never to be repeated.
The slave trade was one of the UK's darkest chapters, the peer said
In doing so, she called for people to remember that millions of people today - mostly women and children - remain enslaved around the world.
These sentiments were echoed by the Ghanaian president who condemned the "nightmarish travesty against humanity".
Referring to calls for reparations for the victims of slavery, he said such an approach would be problematic.
Instead, he called for remorse and a clear understanding of the role played by Europeans and the Africans who helped the trade by selling their own people.
Elmina Castle, which was built by Portuguese traders in the late 1400s before being taken over by the Dutch and later the British, was capable of holding 1,000 male and female slaves at one time.
Poet Linton Kwesi Johnson said it was an opportunity to remember
It remains a striking reminder of the suffering caused by the slave trade and provided a poignant backdrop for the commemorative event.
In the building's main courtyard, away from the dark, cramped cells where hundreds of shackled men and women lived the ceremony gathered pace as dancers clad in blue and yellow gowns provided an enactment of how slavery began.
Chanting songs of praise to the beat of ever present drums, they swayed as the audience clapped and dusk descended.
The event has drawn on poetry and music by a diverse range of artists, many of whom have spoken passionately about their desire to be involved in the ceremony.
It brought together a wide range of artists from Africa and other parts of the globe.
Performers included Jamaican Linton Kwesi Johnson, South African musician Hugh Masekela and Ghanaian hiplife artist Obour.
The spirit of unity between Africans and the descendents of slaves was summed up when the London Gospel Choir was joined by Ghana's Winneba Youth Choir for a rendition of When The Saints Come Marching In.
Bazil Meade, 56, leader of the British choir, said it was the first time he visited Ghana.
Mr Meade, from Chingford, London, said he cried when he visited the cells in Elmina Castle as it came as a stark reminder that his ancestors had been slaves.
The singer, who was born and raised on the Caribbean island of Montserrat, said: "My forefathers were left to sleep in their own faeces for months on end in chains.
"They survived all of that and I am here because of them."
He said he hoped efforts would be made to educate young black people in the UK and other people within the diaspora to build stronger ties with Africa.
"Black Britons may be born in the UK but that is not their cultural history. They need to embrace their history.
"There needs to be a balance between the culture they live in and the knowledge of their roots which will provide a foundation for life."
Kwesi Johnson, speaking shortly before his performance said: "We need to remember the past as a way of informing our future.
"I feel like I'm part of a family and this is a family get-together," he said, explaining that as a Jamaican he considered Ghana to be his "ancestral homeland".
The poet, who said he had been "honoured" to be involved, added that it was also "an important opportunity to remember all those heroes and heroines who gave their lives for the struggle for freedom".