The trek to Pin Bhabha Pass and Pin Parvati Pass is challenging and requires a high level of fitness, endurance, skill and discipline for crossing these two passes back to back. Pin Bhabha pass is a cross over pass from Kinnaur Valley to Spiti Valley and Pin Parvati pass is a cross-over from Spiti Valley to Parvati Valley. After crossing the Pin Bhabha Pass, the trail to Pin Parvati pass starts in Kaza, and ends in Barshaini, which is in Parvati Valley. The terrain changes from lush green Kinnaur to the moraine and scree of Spiti and then again, to the lush green Parvati.