In ancient times, however, when the Temple was still standing in Jerusalem, Sukkot was probably the most popular Jewish holiday - so much so that it was called simply Ha Chag - "The Festival." As one of the three pilgrim holidays, it was the one holiday that everyone wanted to celebrate by coming to Jerusalem, even those Jews who lived in Egypt or Babylon.
After the seriousness of the High Holidays (Sukkot happens five days after Yom Kippur), it was a time of ceremony - of Temple sacrifices by day and great frivolity by night.
The "Rejoicing at the Place of the Water Drawing" was a nightly occurrence that is described in the Talmud:
"Whoever has not seen 'The Rejoicing of the Water Drawing' has never seen rejoicing in his life. At the end of the first day of 'Ha Chag,' the priests and the Levites went down to the court of the women, where they had set up a great structure: There were gold lamps with four gold bowls on top of each one and four ladders to each bowl and four youths from priestly families holding jars of oil … which they poured into the bowls. There was not a courtyard in Jerusalem that was not lit by the light of the place of the water drawing.
"Men of piety and good deed used to dance in front of them juggling lit torches in their hands, signing songs and praises - and Levites without number with harps, lyres, cymbals, trumpets and other musical instruments." (Babylonian Talmud Sukkah 51a-b)
Sukkot has Messianic connections as well.
According to tradition, the Messiah will come at Sukkot, and will usher in a time of peace: "And it shall come to pass that everyone that is left of all the nations that came against Jerusalem shall go up from year to year to worship the King, the Lord of Hosts, and to keep the feast of Sukkot."