It takes place in Coll de la Botella. This is the Pal side of the telecabin, saying that it sometimes can change depending on snow conditions. Depending on the weather they run it different times, some times morning sometimes afternoon. It usually is in the day time though as you need to ski to get to it so it has to be when the slopes are open. Best thing to do is to ask at the Vallnord information desk when you arrive, it's the one at the top of the gondola. From there you can book for activities and they can let you know the times and days it's running for the week your here.