Matthias Church, with the bright color of its tiled roof and its fantastic Neo-Gothic ornamentation, is one of the stand-out attractions of Castle Hill. Most of it dates from the late 19th century, but parts of the church are much older than that. It's named the Matthias Church because King Matthias I married Beatrice of Naples here in 1474.
It was here, in 1867, that Franz Liszt's Coronation Mass was first performed, and the church still has a strong musical tradition; try and catch a concert here if you can.
On the exterior of the church, check out the unusual diamond-patterned tiles of the roof and the Matthias Tower, which bears the king's crest animal, a raven with a gold ring in its beak. Also look out for the medieval columns on the bottom of the Béla Tower, with their studious monks and devilish animals.
Inside the church you'll find rich frescoes and a legendary Madonna statue - this Virgin is said to have saved the Castle from Turkish invasion when her face, revealed by a demolished wall, frightened them into retreat.
You can get to the Matthias Church on buses 16 and 16-A116.