This symphony was written in 1886, so it is from the Romantic period:
As is typical of the Romantic period, there is a huge orchestra, but the unusual additions here are piano and an organ. This performance is from the Proms, so was performed in the Royal Albert Hall, which has a huge (and very loud) pipe organ. You will notice that the organist has to sit with his back to the conductor – he has a rear-view mirror so that he can see what’s going on.
If you think you’ve heard this music before, it might be because it was adapted for the film Babe:
Hayes Music blog 