For someone who hasn’t been there it is unfathomable to see the giant block of rock and ice because we do not have anything that is remotely similar in our normal lives.
I have spend a fair time in the Alps and I have seen some impressive sides but this is different. This picture, taken from the so-called fairy meadow national park was taken at an altitude of 3,300 meters. The collossal mountain in the back is 8125 meters high. That is a difference of 5 kilometers and direct line would be some 12 kilometers from the meadow to the summit.
Nanga Parbat is high. Not just high but really high. At this point the oxygen is 7.5% instead of the normal 20% it usually is. You have less than half the amount of oxygen available. (Though the relative percentage is still 21%, there is just so much less air available in total). At the same time you are doing a very demanding tour in dangerous and cold weather. So you have less energy available and need more.
This height ist dangerous because you die from it. You can get altitude sickness from 3000 meters and up.
HACE = High Altitude Cerebral Edema
HAPE = High Altitude Pulmonary Edema
At such altitudes the pressures and not enough to sustain normal body homeostasis. The lack of oxygen in the brain leads to a reflectory vasodilation in an effort to allow more blood flow into the brain but this leads to edema. The brain is obviously in the skull and this results in a pressure increase that damages the brain. The same mechanism happens inside your lung although this starts because some arteries constrict first (A mechanism to prevent blood flow into unventilated areas but if too many do that the pressure will increase and again, edema). You literally drown at 8000 meters.
At altitudes >7000 meters the body is dying on rates. Your entire metabolism shuts down, sleep is impossible, your gastrointestinal system stops working. No more energy gets to you, you can’t recover.
So did you ever try a super high mountain (which takes a lot of energy every time) while your body is dying and you become delusional from lack of sleep.
And that is just your own limitation.
The most common climb follows through the Kinshofer route in the Diamir flank. You do not risk the huge Rupal flank on the other side and do not spend as much time at the altitude than if you were to repeat the Hermann Buhl walk.
That would be #red. It is extremely steep and avalanches come frequently. The weather is extremely unstable and can turn extremely cold and windy.
If you survive all of that, good luck getting down again.