To label a running event as “tough”, there are some criteria that must be met. Such a footrace should include steep ascents and descents, unforgiving temperatures, intense terrain and extremely long distances. Participants are sure to be pushed to the brink physically, mentally and emotionally. Participants spend quite some time training but only the most ambitious athletes endure to the end. Here are five of the toughest running events in the world. Who knows, you just might be inspired.

1. Badwater Ultra

The Badwater Ultramarathon is often described as “the world’s toughest foot race”. This annual event is a 135 mile race from Badwater basin in California’s Death Valley at 282 feet below sea level to Whitney Portal at an elevation of 8360 feet. Racing in temperatures of approximately fifty degrees Celsius through a desert is certainly no walk in the park. To qualify to participate and face the brutal landscape and unforgiving weather conditions, athletes must finish at least three running races of 100 continuous miles or longer, at least one of them in the previous thirteen months.

2. Marathon des Sables

Marathon des Sables is one of the toughest and sweltering running routes in the world.  It is located in the middle of the Sahara Desert. The race’s overall length varies from 150 to 156 miles each year and is divided up over six days with only one day allotted for rest- typically after the longest section. Extreme conditions of approximately forty degrees Celsius during the day and temperature about five degrees Celsius at night make it even more challenging. Each starter is given survival supplies which include food, a snake bite kit and a sleeping bag which he must constantly keep with him.

3. Jungle Marathon

The Amazon Rainforest is a breathtaking place but the competitors in the Jungle Marathon certainly do not have time to take in the natural beauty and wonders that this rainforest offers. The jungle marathon is a 230 km long extreme foot race through the protective Tapajos National Forest in the Amazon Rainforest in Brazil. The tremendous desire for many ultramarathon runners for a new challenge in an extreme setting birthed this annual marathon. Participants must be mentally and physically prepared for mountain valleys, choking humidity, deep mud, torrential rainfall and the darkness of the night. They are equipped with a survival kit for the long run which is split into five stages.

4. Ultra Trail du Mont Blanc

Every August, in the border triangle of France, Switzerland and Italy, the most challenging running competition in Europe is held. The ancient Olympic town of Chamonix in the French Alps serves as both the starting and finishing location of the 166 km long race around Mont Blanc. Participants must first qualify in a number of competitions. The Ultra Trail du Mont Blanc is one of several races during the week-long festival. The runners cover the distance hitting 10,000 feet of elevation a few times on the way.

5. The Last Desert

The Last Desert held on the continent of Antarctica is a multi-day race and is one of the most incredible journeys. Starting in the Argentine city of Ushuaia, racers sail via the renowned Drake Passage to various spots in Antarctica and nearby islands. The Last Desert is a six-stage 250 km foot race which can be quite challenging given the environmental conditions faced. Those who wish to participate must have competed in at least two of the four Deserts Race Series competitions namely the Atacama Crossing, the Gobi March and the Namilo Race.