The ruins of Cong Abbey, a former Augustinian abbey, date mainly to the 13th century and showcase some of Ireland’s finest medieval ecclesiastical architecture.
A church was first built here in the 7th century, reportedly by Saint Feichin. After a fire in 1114, Turlough Mor O’Connor, High King of Ireland, refounded the abbey, which was later destroyed in 1137 and rebuilt in 1138 as an Augustinian settlement. His son, Ruaidrí Ua Conchobair, Ireland's last High King, expanded it in 1198 and spent his final years there.
The O'Duffy family was closely linked to the abbey from 1097 to 1501. Archbishop Muireadhach Ua Dubhthaigh, who died there in 1150, is commemorated on the Cross of Cong. The abbey was reconstructed in 1307, dedicated to St. Mary, and suppressed after 1542. Its last nominal abbot, Patrick Prendergast, preserved the Cross of Cong before his death in 1829. Benjamin Guinness initiated its restoration in 1855.
Cong Abbey features exceptional early Gothic architecture, including a 13th-century church, cloister fragments, and finely sculpted doorways. A monks' fishing house, likely from the 15th or 16th century, sits over the River Cong, with a trapdoor for fresh fish and a rumored line to the monastery kitchen.
Visby Cathedral (also known as St. Mary’s Church) is the only survived medieval church in Visby. It was originally built for German merchants and inaugurated in 1225. Around the year 1350 the church was enlarged and converted into a basilica. The two-storey magazine was also added then above the nave as a warehouse for merchants.
Following the Reformation, the church was transformed into a parish church for the town of Visby. All other churches were abandoned. Shortly after the Reformation, in 1572, Gotland was made into its own Diocese, and the church designated its cathedral.
There is not much left of the original interior. The font is made of local red marble in the 13th century. The pulpit was made in Lübeck in 1684. There are 400 graves under the church floor.