Place: Dublin Castle
Earning the top slot among attractions in the capital city of Dublin and situated right in the center of the historical city, Dublin Castle is the best preserved castle in Ireland. Employed as a governmental building, the fort is believed to have been build in 13th century around the time of King John, the first Lord of Ireland. Interiors of the castle are all lavishly decorated and will leave you stunned with its shine and glare. Saint Patrick's Hall, Throne Room, and State Corridor are the main attractions of the castle.