On the 31st, J and I wandered down to the town square before midnight. The photo below shows the square just before the masses arrived. All ages were there but drunken teenagers predominated. Fireworks were everywhere and the square resembled a war zone filled with smoke while people popped champagne bottles and hugged and kissed their friends. Also showed is a daytime scene of the square.
Apparently Prague was well prepared for the partyers from all over Europe. A and N watched a fireworks show on the river and then converged with thousands to Wenceslas Square. There was music everywhere, fireworks tossed indiscriminately, impromptu stands selling champagne bottles, drugs peddled openly, etc. The crowds included tourists from all over. The whole city centre was shrouded in smoke. They saw fire fighters on every corner but not so many police. There was a casualty tent with cots and paramedics at the ready. All in all, all festive occasion.