Some useful information that will help in planning for Rush Lake trek 
Possible itineraries
From Hopar village, there are 3 possible itineraries to reach Rush Lake:
2 days trek:
- Hopar to Baricho Kor
- Baricho Kor - Rush Lake
I opted for 2 days approach to the lake
3 days trek:
- Hopar to Barpu Giram
- Barpu Giram to Chedan Harar
- Chedan Harar to Rush Lake
4 days trek
- Hopar to Shishkin
- Shishkin to Barpu Giram
- Barpu Giram to Chedan Harar
- Chedan Harar to Rush Lake
Now coming back has also many possibilities. Either follow one of the above treks to use same route or change your route as follows:
Option 1
- Rush Lake - Phai Pheri
- Phai Pheri - Hamdar
- Hamdar to Hopar[B]
Option 2
[/B]- Rush Lake - Miar
- Miar to Hamdar / Hapakund
- Hamdar / Hapakund to Hopar
You can also go all the way to Hopar on day 2 here
I opted for Option 2 with 2 days approach:
Rush Lake - Phai Pheri - Miar
Miar - Hamdar - Hopar
However, we couldn't cross Miar glacier as weather was very hot and glacier was getting very thin with danger of breaking. So, we went down to Phai Pheri but continued on same side through old route.[B][B]
Stage wise distance, trek time and altitude change
1- Hopar - Shishkin:
[/B][/B]Hopar village = 9,250 ft ASL - 36?12'53.50"N, 74?46'8.97"E
Shishkin campsite = 9,000 ft ASL - 36?12'49.00"N, 74?46'54.33"E
Hopar - Shishkin distane = 1.8 km
Time taken = 1 hour
From Hopar Village, u lose immediately 500ft altitude to go down to Hopar (Bualtar) glacier and then u have to cross the glacier. Glacier crossing is almost 1 km and there is no change in overall altitude though u have to go up and down lots of times while crossing it. Then around 200 ft climb till the campsite. It can be your first rest point.[B][B][B]
2- Shishkin - Barpu Giram
[/B][/B][/B]Shishkin campsite = 9,000 ft ASL - 36?12'49.00"N, 74?46'54.33"E
Barpu Giram campsite = 9,650 ft ASL - 36?13'6.19"N, 74?48'37.32"E
Shishkin - Barpu Giram distance = 3.5 km
Time taken = 2 hours
After Shishkin campsite, there is a 500 ft climb till the ridge of the glacier through a corridor with big stone walls on both sides. This is a steep climb and takes u to the starting point for crossing Barpu glacier. Though Hopar glacier crossing is not technical at all but there are 2,3 points where u have to climb or descend fast or ice starts to get displaced. But Barpu is very straightforward crossing with simple walk. This one is 1.2 km long crossing and takes 30-40 min to cross. After that there is a straight walk till Barpu Giram on left side of glacier wall. You cannot see the glacier as wall is around 200 ft high and glacier is on other side. The distance is around 1.5 km from end of glacier crossing till campsite.
[B][B][B]
3- Barpu Giram - Barichokor
[/B][/B][/B]Barpu Giram campsite = 9,650 ft ASL - 36?13'6.19"N, 74?48'37.32"E
Barichokor campsite = 10,500 ft ASL - 36?11'0.17"N, 74?50'40.98"E
Barpu Giram - Barichokor distance = 5.25 km
Time taken = 1.5 hours
After crossing Barpu glacier, u enter the most boring and ugliest of the treks. It passes through dry land, sand giving look of desert, bushes, pale grass which is hardly surviving and stones and boulders. View is blocked on both sides as on left side is the huge ridge leading to Rush Lake while on right side is glacier wall. Only good scene is looking back at Ultar massif which only becomes visible after gaining some altitude beyond Barpu Giram. Overall, it is an easy and simple walk till Barichokor. Barpu Giram campsite is half dull green and half sandy and no water is available here. There is only one good green patch during this part which is called Joot (جت with paesh) and it is quite long but again no water here. Finally the campsite arrives which is again hardly grassy but there are few bushes and trees and a small water stream coming from Usaimal. This stream gets dried up while crossing Joot.[B][B][B][B][B]
4- Barichokor - Chedan Harar
[/B][/B][/B][/B][/B]Barichokor campsite = 10,500 ft ASL - 36?11'0.17"N, 74?50'40.98"E
Chedan Harar campsite = 14,300 ft ASL - 36?11'8.14"N, 74?52'1.06"E
Barichokor - Chedan Harar distance = 4.5 km
Time taken = 4.25 hours
Now easy stuff is over. This stage starts with climbing straight up on left side ridge to go on top of the mountain. The very first step of this part of trek is to gain altitude at steepest of the levels and it continues for quite some time. It is around 3.2 km till the top and time taken was 2.5 hours. After that half hour rest and then further coverage of 1.3 km in 1 hr 45 min. The moment u reach the top of the mountain, your altitude is 13,200 ft ASL. So, u r almost climbing 1000 ft in every km which is very tough ask. Lots of energy consumed and stressed load on knees and leg muscles. Once you get on top then there is a good news and a bad news. The good news is that now u will walk in open grassy place towards Chedan Harar but bad news is that now altitude is too much and u cannot enjoy your trek without hard breathing :)[B][B][B][B][B][B]
5- Chedan Harar - Rush Lake
[/B][/B][/B][/B][/B][/B]Chedan Harar campsite = 14,300 ft ASL - 36?11'8.14"N, 74?52'1.06"E
Rush Lake = 15,400 ft ASL - 36?10'24.64"N, 74?52'58.81"E
Chedan Harar - Rush Lake distance = 2 km
Time taken = 1.75 hours
The route is comparatively straight after Chedan Harar campsite but it keeps climbing in open space. But the killer is last pass near the big mountain which is a steep climb towards the very end of the trek and is the last tough task to complete. The pass is at 15,500 ft ASL and then there is a long walk till the lake for which u r not left with any energy after doing this pass
Since i was coming from low altitudes and i started at 10,500 and now was entering 15000+ zone so it was natural that breathing becomes very heavy and difficult as gaining 5000 ft in one day is not a good idea 
When i was climbing the final pass i sent my porters ahead as i was getting very slow around 15000 ft mark so they carried on towards the lake and i kept my own pace. I reached Rush Lake in 6 hours.
[B][B][B][B][B][B]
[B]6- Rush Lake - Phai Pheri
[/B][/B][/B][/B][/B][/B][/B]Rush Lake = 15,400 ft ASL - 36?10'24.64"N, 74?52'58.81"E
Phai Pheri campsite = 11,300 ft ASL - 36? 9'23.32"N, 74?52'5.61"E
Rush Lake - Phai Pheri distance = 3.5 km
Time taken = 3 hours
No trek ... absolutely no trek at all !!!
Kind of a mistake to use this route but Alhamdulillah reached the destination safely. My porters told me that hunters use this route in winters :ootherwise nobody climbs it. It was extremely steep descend and we had to choose our own route. It was steep slope all the time till we reached Phai Pheri. The condition of route was changing after every few moments like sometimes grass, then boulders then dirt trek ... in short all variety. Not recommended for Rana sahib at all
In last half hour, u start to see some path near the bushes but again steepness kills the joints. [B][B][B][B][B][B][B][B]
7- Phai Pheri - Usaimal
[/B][/B][/B][/B][/B][/B][/B][/B]Phai Pheri campsite = 11,300 ft ASL - 36? 9'23.32"N, 74?52'5.61"E
Usaimal campsite = 10,800 ft ASL - 36?10'28.12"N, 74?51'5.08"E
Phai Pheri - Usaimal distance = 2.75 km
Time taken = 1 hour
We had plans to cross Barpu and Miar glaciers and camp at Miar campsite across the glaciers. But a baba ji just came back from glaciers and he informed us that Miar cannot be crossed at the moment due to hot weather as ice layers are getting thin and there is chance of surface break. So, we had to change the route and use the same approach from where we came. But instead of camping at Barichokor, we camped at Usaimal which is on higher ground and is source of fresh water. My porters made chapatis here when we camped at Barichokor.
Usaimal is the best camping site in this whole trek on this side of glaciers. Though i have heard that Hamdar is just awesome to camp and it is green with superb views. But it is on other side of glaciers and was missed in this trip.
I saw 2 shelters at the top near Rush Lake and 2 bakarwal houses here in Usaimal otherwise there isn't any population in this area. There are few houses in Hamdar and Hapakun on other side of glaciers. There were few boundary walls in Barpu Giram but nothing else.[B][B][B][B][B][B][B][B][B]
8- Usaimal - Barpu Giram
[/B][/B][/B][/B][/B][/B][/B][/B][/B]Details are already mentioned above. I will only mention time which was 1 hour from Usaimal till Barpu Giram.
[B][B][B][B][B][B][B][B][B]
9- Barpu Giram - Shishkin
[/B][/B][/B][/B][/B][/B][/B][/B][/B]Time taken = 1.5 hours[B][B][B][B][B][B][B][B][B][B][B]
10- Shishkin - Hopar Village
[/B][/B][/B][/B][/B][/B][/B][/B][/B][/B][/B]Time taken = 1.25 hours
Hopar glacier was misbehaving a bit due to very hot weather and ice was getting soft at places so we had to be extra careful while crossing this one. My porter told me that sometimes we have to change the route with a long diversion of 2 hours if this route gets disturbed due to weather.
