The Gadsar Pass is the highest point of the trek at 4,180 m, and day 4 is built around it. You leave Vishansar Lake at 3,663 m and end the day at Gadsar camp, at 3,386 m. The walk is 6 to 7 hours and about 11 km, and it is the longest day of the trek.
From camp you can see the route before you set out. The trail shows as a thin line of switchbacks on a bare, brown mountain, and it looks harder than it is. First you walk past the twin lakes of Vishansar and Kishansar, with Kishansar at about 3,820 m. Then the climb starts, and it is steep.
There is one rule that works for this climb: look at the next few steps, not the top. Stop when you need to. Once you are on the slope, turn round every so often. Both lakes lie below you, and the view only gets better the higher you go.
The descent on the other side leads down to Gadsar, where the lakes of the Gadsar group lie in a green valley. It is a long drop, and the knees notice it, so poles help.
What to expect. The pass is a grassy and rocky climb, not a technical one. In July some snow can remain near the top. If it does, we carry the gear for it and use it as the conditions need.
Weather. August brings heavy rain in Kashmir, so we plan for an early start. If the weather is poor, the guide will tell you when to turn back, and we follow that call.
This is also a good day to understand the trek's pacing. It follows two nights below 3,700 m, which is why the climb, hard as it is, stays within what a generally fit walker can manage.