Over 20,000 Thai and foreign tourists have already booked rooms in various hotels in the province where the grand event kicks off tonight.Meanwhile,Lord Mayor of the province said that this year the festival would be bigger then that of the previous years.The highlight of the event would be the colour and light decorations all over the city.Also included in the event would be the world's biggest floated in lantern to be released into the sky while big lanterns would be also floated in the rivers.In addition,a lantern contest would be hald to entertain the enthusiastic spectators.