Americans headed to popular mountain region face travel advisory for natural disasters and unrest

The advisory decreased to a "Level 2: Exercise Increased Caution," following the end of nationwide protests that began in September.

"The situation is stable," the advisory noted. 

"However, demonstrations and local unrest can still happen, particularly in cities."

Officials note that demonstrations may still occur with little warning and can "quickly turn violent."

"Stay away from large crowds and follow the instructions of local authorities," officials advise.

"These can block roads, damage buildings and make it hard to get help in an emergency."

The Kathmandu Valley is located at the foothills of the Himalayas and is a UNESCO World Heritage site.

These are the Durbar Squares of Hanuman Dhoka (Kathmandu), Patan and Bhaktapur; the Buddhist stupas of Swayambhu and Bauddhanath; and the Hindu temples of Pashupati and Changu Narayan, according to UNESCO.

About 700 to 1,000 climbers attempt the summit each year, with success rates ranging between 60% and 70%, according to Climbing Kilimanjaro. 

That's where the air is too thin to support human life without supplemental oxygen.