We've been to Bayreuth only once (a guest of one of our father's business associates): in the late '50s where we saw part of the Wieland Ring (his original staging). We really couldn't appreciate what we were seeing then as at that time in our life we thought Wagner a vulgarian, his operas (that's what we called all his stageworks at that time making no distinction between his operas and his music-dramas) even more contemptible than Italian opera. From that experience we can attest to the following by Mark Twain (c. 1891), perhaps the most perfect, the most poetic description we've ever read of the experience of the "old" Bayreuth (i.e., "old" as opposed to the Bayreuth of the 21st century):
All the lights were turned low, so low that the congregation sat in a deep and solemn gloom. The funereal rustling of dresses and the low buzz of conversation began to die swiftly down, and presently not the ghost of a sound was left. This profound and increasingly impressive stillness endured for some time — the best preparation for music, spectacle, or speech conceivable. [...] Finally, out of darkness and distance and mystery soft rich notes rose upon the stillness, and from his grave the dead magician began to weave his spells about his disciples and steep their souls in his enchantments. There was something strangely impressive in the fancy which kept intruding itself that the composer was conscious in his grave of what was going on here, and that these divine sounds were the clothing of thoughts which were at this moment passing through his brain, and not recognized and familiar ones which had issued from it at some former time. [...] Yesterday the opera was "Tristan and Isolde." I have seen all sorts of audiences — at theaters, operas, concerts, lectures, sermons, funerals — but none which was twin to the Wagner audience of Bayreuth for fixed and reverential attention, absolute attention and petrified retention to the end of an act of the attitude assumed at the beginning of it. You detect no movement in the solid mass of heads and shoulders. You seem to sit with the dead in the gloom of a tomb. You know that they are being stirred to their profoundest depths; that there are times when they want to rise and wave handkerchiefs and shout their approbation, and times when tears are running down their faces, and it would be a relief to free their pent emotions in sobs or screams; yet you hear not one utterance till the curtain swings together and the closing strains have slowly faded out and died; then the dead rise with one impulse and shake the building with their applause. Every seat is full in the first act; there is not a vacant one in the last. If a man would be conspicuous, let him come here and retire from the house in the midst of an act. It would make him celebrated. [...] This opera of "Tristan and Isolde" last night broke the hearts of all witnesses who were of the faith, and I know of some who have heard of many who could not sleep after it, but cried the night away. I feel strongly out of place here. Sometimes I feel like the sane person in a community of the mad; sometimes I feel like the one blind man where all others see; the one groping savage in the college of the learned, and always, during service, I feel like a heretic in heaven. But by no means do I ever overlook or minify the fact that this is one of the most extraordinary experiences of my life. I have never seen anything like this before. I have never seen anything so great and fine and real as this devotion.