This day starts early with hotel pickups in the center of La Paz from 3am to 4am and then the bus will be leaving for Oruro. The journey to Oruro takes around 3.5 to 4 hours so you should arrive at the carnival site at around 8am. Please note that many thousands of people will be travelling this day so some delays are possible and this arrival time is approximate. You will be served a basic traditional breakfast (included) and lunch (not included) will be available to purchase during the tour in Oruro. Once you have arrived to Oruro your guide will escort you to your carnival seats and issue you with your water poncho.
From you carnival seats you will be able to see the processions of dancers in traditional costumes performing a variety of traditional Bolivian dances. As the day moves on the carnival atmosphere will get livelier and livelier. There will be lots of vendors selling soft drinks and beers throughout the day
For the return journey to La Paz the bus will depart at approximately 23.00 arriving at around 2/3am (your guide will inform you of the return departure time on the day and the meeting point - please note these these times may change by an hour or so).
You can watch a video for the Oruro Carnival Bolivia here to get a good idea of the Oruro Carnival atmosphere:
There are some good photographs of the Oruro Carnival on the BBC website also.