We recommend that you purchase a 1.5 – 2 liter bottle of water to take with you on the first day. Every night during the trek, we will boil water so you can refill the same bottle every morning before setting out. If you are planning to drink from any streams or waterfalls, we strongly suggest you bring water purification tablets or filters. Also, you will be able to buy water along the way on Day 1, for the first few hours of Day 2, then again on the afternoon of Day 3, and of course at Machu Picchu.