One of the toughest winter treks, this route is very popular among regular trekkers. While you can also try this trail in summer, in winter, the snow adds to the route's challenge and thrill. The route to Sankri village is a trekker's paradise. With rivers like Tons, Yamuna and Kedarganga as your companions, the road passes through lush pine forests and lofty peaks. Early morning, you will leave for Sankri village from Dehradun and will reach by the evening. In between, you can stop for breaks in the lush landscape. The night stay will be at Sankri, which is the gateway to the Govind National Park and Wildlife Sanctuary. Sankri is the base camp for several popular treks including Kedarkantha, Har ki dun and Rupin pass.

Starting the trek from Sankri, you will have to reach Seema village on the second day. This will include a 14-km trek and a short drive. After breakfast, you can start your drive to Taluka village, when where the trek will begin. The trekking route passes through lofty pine and deodar forests, with the Supin river rippling along with you. After almost a 14-km hike, you will arrive at Seema, where you will be camping for the night. 

After an early morning breakfast, you can start your trek of around 13 km for the day. The scenery changes as green pastures take over from forests. You can stop at Debshu Bugyal, a small scenic meadow that offers jaw-dropping views of snowcapped peaks like Kala Nag. On the way, you will cross the Supin river and then reach the campsite of Rainbasera.

After breakfast you will start your trek to the Ruinsara tal, which itself is a popular trekking destination. The trek will cover around 8 km and can be completed in about five hours. The Ruinsara tal is a serene glacial lake surrounded by mountain ranges and meadows and the route offers stunning views of the peaks of Bandarpoonch, Kala Nag and Dhumdhar khai. The night stay will be at Ruinsara.

After breakfast you will start the day's short trek of just 4 km to Odari. The trail goes down to Supin river over a bridge and then up another meadow. At the end of the meadow is the natural rock cave Odari. This is where you will be camping for the night. Local legend says this was the place where King Bali from Hindu epics stayed for one night before crossing the Bali pass. The trek of around 2 hours is a welcome break in the long and challenging route.

After breakfast, you will start the trek to Bali pass base-camp (4678 m) and this stretch is the most challenging. The trail is very steep and you gain significant height. Keep drinking water to stay hydrated. Remember to take proper precautions to avoid Acute Mountain Sickness (AMS). While the distance is around 5 km, the time taken to cover the same will depend on your physical fitness. The night temperature dips to sub-zero.

Start your last day of the trek early. You will have to climb 600 m and then descend 1,524 m through a challenging terrain. The snow-covered trail up to the pass is steep and it generally takes around 3 hours to reach the pass. You will also need to use micro-spikes. The pass (4,950 m) is around 3 m wide and 1 km long and the surrounding views are spectacular. Gaze upon the Swargarohini and Banderpooch massifs, the Yamunotri valley and the complete Garhwal range, including Nag Tibba. The view is breathtakingly beautiful. After the pass, the descent is also challenging. Stop for a break at Upper Dhamini, from where the trail goes down to a meadow. The trek to the campsite at Lower Dhamini is not for the faint hearted and it can take upto 6 hours to reach it. The next day, you will walk down an easy path to Janki Chatti and then drive to Dehradun.