Basilica of Esztergom
Esztergom was the medieval capital of Hungary, sitting on the banks of the Danube River, overlooking Slovakia across the water.  This is one gigantic cathedral- the largest in Hungary.  Construction started in 1823 and the church was consecrated in 1856, where Liszt's Esztergom's Mass was performed (it should be noted that Beethoven had offered to conduct Missa Solemnis for the consecration, but construction took too long to finish).