When planning a trip, it’s essential to take every detail under consideration: how long the flight will last, itinerary, museums, restaurants, hotels. However, many people forget things can affect every aspect of life when traveling - the destination’s altitude.

Cities that are more than 2.400 meters are often found in three regions: the Himalayas in Asia, the Andes in South America and the Ethiopian Highlands of Africa. However, you can also see some of those cities in the United States.

Arriving in a city with a higher altitude can affect your body and cause what is called “altitude sickness,” that used to occur when you travel to a high altitude in a short period. It happens regardless of age, gender, and physical condition. You can notice the problem when breathing becomes difficult; you have a tremendous headache, dizziness, and nausea.

When planning a trip, it’s essential to not underestimate the altitude sickness and always wait for at least 48-hours before doing heavy activities. It also helps to avoid eating red meat, drink a lot of water and eat light meals.

Some people around the world have learned to treat altitude sickness in their way. When travel in Bolivia and Peru, for example, you will notice that coca leaves are the most efficient way to handle it. You can chew the leaves, drink the tea or buy coca candies anywhere.

You don’t have to change your travel destination because of the altitude, but being aware of it can help you to avoid some problems during vacation.

22 20. COLORFUL MOUNTAINS IN COLORADO

Colorado attracts thousands of tourists eager to explore nature and adventure in sports like rafting. Since the mountains are all higher than four thousand meters, it is common that people feel the effects of high altitude. According to University of Colorado School of Medicine, up to 30 percent of visitors suffer from it.

But you don’t need to let it spoil your holidays. Specialists advise staying one or two days in Denver ( where the altitude is 1.731 meters), while the body gets in use to the height and only 10 percent of visitors feel the symptoms. Having Gingko Biloba pills and drinking a lot of water can help to reduce the effects.

21 19. LA PAZ, THE CHAOTIC AND AMAZING CAPITAL OF BOLIVIA

Manage the Spanish language is not the only thing you have to worry if you decide to visit the capital of Bolivia, La Paz. The city is 3,640 meters above sea level, and one of the first words you will learn when arriving in the town is “soroche,” the expression used to altitude sickness.

When you do the check-in at the hotel, they will offer you a cup of coca tea, the best medication you can have for soroche. In fact, when you are at the airport, it’s possible to buy coca chewing gums or candies. It’s also possible to collect some coca leaves and eat them during the day.

20 18. SUCRE, Bolivia - A PERFECT PLACE TO TAKE IT EASY

Sucre, also known as “The White City” is 3.200 meters altitude and is surrounded by the magnificent Andes Mountain Range. The view alone is a great reason to deal with a couple of days of altitude sickness. The city attracts tourists for its architecture and is also the cheapest place to buy traditional souvenirs, especially alpaca products.

Before exploring the old town and their famous cemetery, remember to use coca products and carry soroche pills with you.

The best thing you can do is give a chance to your body get in use to the altitude. If it’s possible, start your Bolivia trip in Santa Cruz de la Sierra (419 meters), then head to Sucre and finish it in La Paz.

19 17. LHASA, THE HEART OF TIBET

Lhasa (3,656 meters) is the political and spiritual heat of Tibet and is one of the most important countries for Buddhists and also for those who want to climb the Everest. Visiting Tibet demands some planning, and you have to ask for a special visa as a tourist. The tourism is also tricky since it is mandatory to hire an agency to do all the tours.

On the top of that, you have to deal with the altitude sickness. Take the acclimatization process serious: drink a lot of water and don’t push your body too hard in the first 48 hours.

Despite the limitations, the country has some of the most amazing temples you will ever see.

18 16. MACHU PICCHU, ONE OF THE SEVEN WONDERS OF THE MODERN WORLD

Machu Picchu, in Peru, was built in the 15th century but was just discovered by explorers in 1911. Today it’s the most famous Peruvian postcard and one of the seven wonders of the modern world.

It’s located 2.400 meters from the sea level and, just as in Bolivia, you can use coca products to relieve the soroche effect. You can also find Sorojchi pills, the most popular medicine to treat altitude sickness, found in any drugstore.

Visiting Machu Picchu is a once-in-a-lifetime experience, but it will demand a lot from your body. Before heading to Machu Picchu, take it easy for a couple of days.

17 15. MOUNT KILIMANJARO, THE ALTITUDE IS NOT THE ONLY CHALLENGE

The name is familiar - and a dream - among the climbers around the world. Mount Kilimanjaro ( 5.895 m), in Tanzania, is the highest mountain in Africa.

The mountain has three altitude zones: High altitude ( up to 3,500 metres), very high altitude (up to 5,500 metres) and extreme altitude (above 5,500 metres). People can face altitude sickness in all of them.

Preparing to climb Kilimanjaro demands more than just peak physical condition. If you can expose yourself to high altitudes before Kilimanjaro, it will be helpful. Make sure you arrive in Tanzania some days before the journey, so your body has the time to adapt.

16 16. SHINGTSE, PERFECT FOR THOSE WHO LOVE TEMPLES AND NATURE

Shigatse (4.320 meters) is another impressive city in Tibet. The highlights are the temples, monasteries, and nature. Tibet is a paradise for climbers and Shigatse doesn’t let them down - many visit the city to climb Kangbala Mountain.

Having an oxygen bottle can be helpful, but don't use it immediately, unless the symptoms are unbearable. Eat food that is rich in carbohydrates and avoid red meat for a couple of days. In Tibet, they advise you not to take a bath on the first day, to prevent catching a cold.

If you have severe anemia, high blood pressure, heart disease or breathing problems, you should reconsider visiting Tibet - or other high places - since the altitude can make those conditions worse.

15 15. HUARAZ, A TREASURE TO BE DISCOVERED

Huaraz (3.025 meters) is becoming more and more popular among the tourists who visit Peru. The region has more than 400 blue or green water lakes, and mountains surround the area. The scenario is a paradise for trekking lovers, but the altitude can make the path more difficult. Going up the Laguna 69 (3,900 meters), for example, takes approximate 4 hours and just 2 hours to come back.

The treks are very demanding, and guides advise to do the easier ones first. Visitors should start with Lagunas Llagunuco or Paron and save Laguna 69, the most difficult, for the last day.

14 14. TILCARA, ONE OF THE MOST IMPORTANT ARCHEOLOGICAL SITES IN ARGENTINA

Tilcara (2.465 meters), in Argentina, is another famous city you might feel altitude sickness. The town is renowned for Pucara’s archeological site and is another excellent place to buy souvenirs.

There is also a “curse” involving the city. Back in 1986, the Argentinian soccer team went to the town to train for the world cup. The coach went to a church in the city and promised he and the whole team would go back there to thank God in case they won the World Cup. They won the tournament that year but never came back. Since them, they never won the World Cup again, and people in Tilcara strongly believe that’s the reason.

13 13. SHANGRI-LA, A PLACE WITH CONNECTION TO HEAVEN

Shangri-La (3.160 meters), in China, received this name officially in 2001 since people believe it was the city described in James Hilton book, “The Lost Horizon,” that tells about an idyllic place lost in the middle of the Himalayas.

There is a reason to believe it’s true. Shangri-La is a perfect destination for people looking for a spiritual experience surrounded by mountains and forest. The city has a Tibetan architecture, and the streets are decorated with the Tibetan flags. However, you will likely feel some difficulties breathing when you arrive, due to the altitude. Breathing slowly and not walking too much can help you feel better soon.

12 12. MOUNT KENYA, THE EXTINCT VOLCANO

Mount Kenya (5,199m), an extinct volcano, is the second highest mountain in Africa, just after Kilimanjaro and is one of the main attractions in the country. The region is wilder and less explored than Kilimanjaro and most people who visit the area have a main target: summit Mount Kenya.

There are different options for those who want to climb, and it usually takes 5 to 8 days. Depending on the patch you choose. It’s important to arrive a few days before start the adventure and also bring proper altitude sickness medication with you. Before deciding on which company you'll choose to go with, make sure they have an appropriate structure to help people in case they feel altitude sickness.

11 11. ADDIS ABABA, YOUR FIRST STOP IN ETHIOPIA

Addis Ababa ( 2.355 meters) is the capital of Ethiopia and is usually the first city people visit when they decide to explore the African country. The tourism in the region is increasing recently, and they have a lot to offer: temples, caves, mountains, isolated tribes, to name a few.

The first contact with Addis Ababa can be impacting. The traffic is chaotic, the dry climate combined with altitude sickness can make you feel a little bit lost at first. But walking in the city center, going to the National Museum and hiring one of the many tours they offer is essential to understand more about their beautiful culture and recent history.

10 10. SAN PEDRO DO ATACAMA, THE DRIEST DESERT IN THE WORLD

It’s impossible to think of Chile and not visualise one of the most impressive and driest regions in the world - San Pedro de Atacama ( 2,400 meters). There you can see the remarkable sunset at the Moon Valley, geysers, flamingos and turquoise lagoons.

Even if you stay a whole week in the Atacama, you won’t be able to do everything. But also if you want to enjoy your holiday to the fullest, take it easy. Book the easiest tours for the first days and always check the altitude. Talk to the agency workers; they will help you do do that. Avoid heavy meals and try to rest as much as you can.

9 9. PASO JAMA, AN UNUSUAL WAY TO TRAVEL FROM ARGENTINA TO CHILE

Paso de Jama ( 4.200 meters) is a mountain pass through the Andes between Chile and Argentina, and the view is breathtaking. It's common that many people travel from Argentina to San Pedro de Atacama Desert using this road and for those who choose to rent a car it’s possible to do the travel at their own pace.

Along the road, you will find many mountains and the landscape views are certainly worth slowing down for. However, if you come from a city with low altitude in Argentina, you might feel the effects of “soroche” during your trip. Avoid traveling alone, and have water and some fresh fruit inside the car.

8 8. SALAR DE UYUNI, A DESERT OF SALT IN THE MIDDLE OF BOLIVIA

If you travel to Bolivia, there are high chances that the reason for your visit is to explçore the Salar de Uyuni (3,656 meters). Many people choose to so the Salar and Atacama together. If your journey has started in Chile, your body will probably be acclimatized to the altitude.

However, if you start the trip in Bolivia, wait two days before heading to the salt flats. It’s better to feel the soroche in a city in La Paz, than during your tour. The tours at Uyuni last from one to three days and the hotels are in the middle of nowhere, so it’s better to take some medication with you.

7 7. ASPEN, COLORADO - GO SLOW WHEN YOU ARE GOING UP

Aspen (2,438 meters) is one of the most famous destinations in Colorado, especially for those who want to spend some days skiing. However, depending on where you come from, you can feel the effects of the altitude. If you have the chance to stop for a couple of days in a city with moderate height, it can be helpful.

If you are not feeling ok, try to rest and avoid physical activities in the first 48-hours. You can also try to go down in altitude and remain there until you feel ok. Try to go up slowly and go at your own pace.

6 6. CUSCO, GETTING READY FOR MACHU PICCHU

Although Cusco and Machu Picchu are 167 km from each other, this is the closest airport to the most famous Incan ruins. People advise staying a few days in Cusco before heading to Machu Picchu. Although the altitude in Cusco is lower (3,339 meters) than at Peru's postcard location, don’t underestimate it. It’s not uncommon for people to arrive in Cusco and start to feel a little sick already.

Like in other cities in Peru and Bolivia, the Coca tea is abundant and helps to deal with the problem. Although there are many interesting ruins and tours in Cusco and its surroundings, spend the first days exploring the old town.

5 5. SANTA FÉ,  WHERE YOU CAN JUST SLOW DOWN

Santa Fé (2,194 meters), is another city in the U.S. where people often can feel sick due to altitude. But the activities in the town are not very physically demanding, so you don’t need to change your itinerary because of it. Santa Fé offers visitors the chance to understand more about Spanish colonization in the region.

Even if you are not a fan of museums, just walking in the plaza, the markets and admiring the details of Santa Fe’s architecture can give you an idea of the Spanish colonization in the city. If you want to understand more about its history, stop by the Palace of the Governors.

4 4. LA RINCONADA, THE HIGHEST CITY IN THE WORLD

La Rinconada attracts tourists for one reason: it’s the highest city in the world (5,100 meters). Although the city receives a considerable number of visitors, the routine and structure of La Rinconada have not improved. Even for those people who come from other high towns in Peru, it’s possible they feel sick when they arrive in La Rinconada.

Most of the inhabitants came from the Puno region and moved there to try to find gold. Due to the lack of hotels, people who visit La Rinconada do a day trip and go back to Puno (where the Titicaca Lake is) or go to Cusco.

Nepal is a paradise for trekking lovers, and Annapurna Base Camp (4,130 meters) is the most famous of them. It is not easy: the trek takes up to 14 days, and people have to be prepared to face different weather conditions.

But people who decide to do it will be gifted with spectacular mountain views. Explore some villages along the way, meet locals and see how they live. The landscape is also unique, and you can see some bamboo and alpine forests.

Although you can book everything online, the best thing you can do is negotiate the price in person.