We didn't do any of the activities or ride the bikes but did find it a great place for hill walking. Lots of options - go up on the gondola and then walk up the peaks and down the pistes and take the gondola back down, (5.80 one way or 10 euro r/t or you can even walk back down all the way to Sispony and over to La Massana ( we covered about 14km doing this). Just be alert to sharing some trails with mountain and motorbikes, and that the free walking map available at the tourist office is absolute rubbish. The map from the gondola ticket desk is slightly better.
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