Penrhyn Castle on the outskirts of Bangor in Wales is owned by the National Trust. In 2007, the bicentenary was marked with a special exhibition and accompanying events exploring the connections between the Castle and the fortune of its former owners, the Pennant family, built on Jamaican sugar from one of the largest estates on the island. The exhibition featured the story of Richard Pennant, 1st Lord Penrhyn, a wealthy merchant and MP for Liverpool who fought against abolition in Parliament. Some of the research was carried out by members of the local community, who were trained in archival research by exploring the Penrhyn Jamaica papers held at Bangor University, which included Richard Pennant's letters as absentee landowner.

The project created links between a local school near the Castle, Banks Road school in Liverpool and Mavisville school in Kingston, Jamaica. All three schools provided art, prose and poetry to the exhibition. Workshops were held for all visiting schools. Accompanying events included art days where a local artist worked with visitors to explore the meaning of landscape painting in the context of slavery; a Caribbean weekend; and a day of activities and workshops with a multi-faith groups of teenagers from Liverpool. A DVD of all the information gathered was given free to schools and libraries.

The Bittersweet programme by the Gateway Gardens Trust involved 80 free guided garden visits over two years, around more than 30 gardens in Wales with a range of community groups, schoolchildren and lifelong learners. The themes of the visits and a mobile exhibition were the links between the slave trade and historic gardens, their makers, what they planted, Welsh abolitionists and the wider links with local communities in Wales. Historic gardens provided the starting point, looking at how everyday vegetables and fruits - beans, potatoes, tomatoes etc. - first reached the UK from the Americas. The project also looked at the history of afternoon tea, and the links between sugar, cotton and tea and slavery. The groups reflected on how many industries, grand houses and gardens were built from wealth linked to slavery, such as Cyfarthfa Ironworks in Merthyr and the expansion of the slate industry at Penrhyn Quarry. Early 18th century-style newspapers were produced, aimed at schoolchildren and adults.

Gardens involved included Cardiff’s Bute Park, Swansea’s Singleton Park, the National Botanic Garden in Carmarthen, Gwydir Castle in Llanrwst, Dyffryn Gardens, Portmeirion, Penrhyn Castle, Picton Castle, Dinefwr Park and Castle and Aberglasney Gardens.