This cathedral in the Italian Renaissance style, designed in 1840 by Joseph Kane, resembles a Greek temple and is surmounted by a tall domed belfry. Inside, the vault is supported by a double row of Ionic columns. In the right transept, the Diocesan Museum houses Saint Mel's Crozier (10C), found at old St-Mel's Church in Ardagh (south-east) in 1860.