You are listening to the famous Hornpipe movement, transposed down a sixth, from D to F Major, with added improvisations occurring before the final recapitulation.
In order to accommodate the large 9+ second full releases of the Esztergom Bascilica, the piece had to be performed somewhat slower than usual, with a detached sense of touch, and with several grand pauses, in order to enable the sound to be intelligible.