The dry season runs from December through to early March. The river will be lower and the track will be less muddy. Some of the river crossings may not even come up to your knees. At other times of the year the river will be flowing faster and deeper. This can be slow going but the guides will use ropes to help you across. On one crossing there’s even a small cable car. A lot of the adventure and the difference from other walks, where there may be bridges and well graded tracks, is crossing the Buritaca River many times.
Going into and out of the Lost City you will cross the Buritaca River almost twenty times. During the rainy season expect at least one downpour a day. That could mean that you’re crossing the river through chest-deep water. You will need to balance your bag on your head or put it in a big plastic bag. The deep water can be a good escape from the heat for a few moments. Parts of the track will also become thick and sticky with mud. Try not to lose your shoes. The 1,200 steps leading up to the ruins will be slipperier than usual if it has rained recently, so be careful how you tread. You will still have plenty of time to see the ruins.
The jungle is always going to be hot at low altitudes. But the elevated camps at night can be quite cool. If you normally feel the cold – check with your tour company to see what blankets they provide and consider bringing your own sleeping bag. Some people will be fine in a sleeping bag liner or a dry set of clothes. While you’re walking it’ll be hot and humid. You’ll be sweating up steep hills and trying not to slip down the other side. In parts of the trail there will be no protection from the equatorial sun so it’s good to have a hat or sun block ready.
Mosquitoes are prevalent all year round on the trail so it pays to have some repellent with you.
The biggest change in the conditions is represented by the river. It can be crossed at all times but it’s just a matter of whether you’re casually walking through or pushing slowly through thick water, trying to keep your bag dry.