Is it safe to drink the water in the Karakoram?

No. Always treat water using a filter, purification tablets, or by boiling it for at least 3 minutes, even at high altitudes.

What is the most dangerous mistake people make?

Ignoring the 'climb high, sleep low' rule and trying to complete a trek too quickly due to limited vacation time.

Preventing altitude sickness in the Karakoram

Prevent altitude sickness in the Karakoram by strictly following a graduated ascent schedule and maintaining hydration with at least 3 liters of water daily. Do not rush your itinerary; your body needs at least 48 hours to acclimatize once you cross the 3,000-meter threshold.

Follow the 'Climb High, Sleep Low' rule. Never increase your sleeping altitude by more than 300-500 meters per day once you are above 3,000 meters. If you hike higher during the day, return to a lower base for the night.
Acclimatize in Skardu or Gilgit. Spend at least two full nights in Skardu (2,200m) or Gilgit (1,500m) before heading higher into the Karakoram ranges. Do not fly into the region and immediately start a high-altitude trek.
Monitor for symptoms. Keep track of headaches, nausea, or dizziness. If symptoms appear, stop your ascent immediately. If they persist or worsen, you must descend at least 500 meters.
Consult a doctor about Diamox. Speak to your GP about acetazolamide (Diamox). If prescribed, start taking it 24 hours before your ascent, usually at 125mg twice a day, to help your body acclimatize faster.

Is it safe to drink the water in the Karakoram?: No. Always treat water using a filter, purification tablets, or by boiling it for at least 3 minutes, even at high altitudes.
What is the most dangerous mistake people make?: Ignoring the 'climb high, sleep low' rule and trying to complete a trek too quickly due to limited vacation time.