1) Be careful with the altitude: it is no mystery that Cusco is located at 3399 MSNM, but for some urban myth many believe that Machu Picchu is higher and it is the other way around, to reach MP you must go down to 2430 MSNM.
Drinking too much, eating too heavy, not hydrating enough, walking too fast are small details that may not normally mean anything to you but here they take their toll.
2) Machu Picchu is not in Cusco city: although it is in the region, there are 100 kms between the historic center and the citadel and it is not a particularly easy journey.
3) Be prepared to get up early: depending on the places you want to visit and in view of the fact that at some times of the year it gets dark quite early, there are tours that leave around 4 am to make the most of the daylight hours.
4) Long lines are common: Machu Picchu, as a wonder of the world, is one of the most touristic places in the world and the demand to visit it is very high, even now that there are more restrictions due to the COVID.
5) Accessibility: unfortunately both Cusco and Machu Picchu, as imperial and colonial cities have a lot of cobblestones, stairs and constructions on terraces and platforms that make it quite inaccessible for people with reduced mobility or baby carriages.
Due to its World Heritage status, the trails are unalterable in order to adapt them to the different mobility needs.
6) Plugs: the plug used in Peru is the one with 2 flat legs and the voltage is 220v (the same as in Chile) do not forget to bring your plug adapter.
I take this opportunity to remind you that electronics such as cell phones, tablets and computers usually have a voltage range of 110v to 220v, but hair dryers, shavers and irons usually do not.
7) Find exchange houses in El Sol avenue: in this main avenue you will find all the exchange houses whether you have brought dollars, Chilean Peso or Euros, you will be able to change without any problem.
8) Credit cards: they are accepted in most restaurants, hotels and even in cabs and even in craft fairs, but it is good to have cash for example to pay for tourist tickets, there I was asked for cash.
If you plan to pay somewhere with a card, ask before consuming to make sure that they accept it and do not have a bad time and let your bank know before traveling that you will be in another country so they do not block your transactions.
9) Stamp your passport: you have surely seen that in Machu Picchu you can stamp your passport with the bell of the citadel.
Indeed this is true and it is done at the exit of the circuit at a window that is before the area where you take the buses down.
But be careful, there are countries that will not allow you to enter them if your passport has unofficial stamps like this one, for example some Arabs. I recommend you to collect this kind of stamps in an old passport to avoid any bad surprises.
10) Buy tickets in advance for capacity: the citadel of Machu Picchu is one of the most visited places in the world and its access is limited to 2000 people per day seems a lot but often it is not enough.
If you want to climb the Wayna or Machu Picchu mountains that capacity is reduced to only 200 people per day, so if you do not buy your access to them a couple of months in advance, it will be impossible to access them. I recommend you to do it on the official website so you don’t end up paying too much.
11) Avoid the Peruvian Winter: between December and March, even the first weeks of April, this phenomenon brings heavy rains to the area.
The town of Aguas Calientes is often isolated by floods that can delay your trip and the tours can not be carried out for this reason.
It is important to keep your passport protected in a Ziploc bag or similar to avoid it getting wet.
12) Unpredictable weather: the dry date from destination is from mid-April to October, being June and July the hottest months and the high season, therefore it is also more crowded.
However, the thermal oscillation can be marked between day and night and evenings can become cold. Pack your luggage with this in mind.
13) What to pack: Considering the above, it is a good idea to pack a first layer and a compact parka.
Sunscreen and repellent are essential, the latter especially if you will do the path of the hydroelectric, that on the banks of the Vilcanota River you can be an easy target for mosquitoes (you can find in local stores at a good price).
14) Fog: it is common that Machu Picchu is wrapped in a dense fog that often makes us think, as we climb, that we spent our savings for nothing.