The trek begins with the fight into Jhomsom from Pokhara. People walk up to Jhomsom all the time for a trek in itself (Kali Gandaki valley trek) and others trek around the whole Annapurna region (A trek called the Annapurna Circuit). People who walk in from Pokhara usually turn around at Muktinath or sometimes at the Thorong La itself (about two weeks).
The Annapurna Circuit starts near Ghorkha on the road between Pokhara and Kathmandu and goes around counterclockwise behind the Annapurna range and back down through Jhomsom and ends at Pokhara (about 1 month). The trek described here, the Jhomsom to Thorong La trek, is a shorter, to the point trek, to see a beautiful piece of the Annapurna Circuit