The roof of North America that is difficult to climb, This is Mount Denali! 

Mount Denali, the highest mountain in North America. Denali's majesty and beauty make it one of the most famous and respected mountains in the world. Mount Denali is not only a symbol of natural beauty, but also a challenge for climbers and scientists interested in studying geological and climatic phenomena in the region.
For more details about Mount Denali, here is the video.