We visited the Basilica and were stunned at how beautiful it was. We also heard the pipe organ and, given the great acoustics in the Basilica, it was worth arranging to be there to hear it. It is quite powerful, and I think the organist likes to make sure people experience that! (I almost jumped when it started to play it was so loud). I don't think a long visit is required, but a short one is highly recommended.
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