Regions in Nepal
Nepal's trekking terrain is divided into a few distinct regions. By far the most popular and heavily traveled is the eastern Khumbu region in the Sagarmatha National Park, home to Mt. Everest and many of the world's top mountain summits. In the central region is Pokhara, which is the gateway to Annapurna and Manaslu. To the far west there are certainly some interesting trails, but it is a much less popular region and there are fewer organized treks. Political circumstances have also cooled the interest of western travelers to that region.
Trekking through Khumbu actually begins as soon as you step off of the airplane at the Lukla airport. Starting at 9,500 feet and hiking in to the entrance of the Sagarmatha National Park you'll immediately encounter the colorful adornments of the Sherpa villages. Your guide will no doubt want to rush you on to the Thursday market there in Lukla or to the Saturday Namche Bazaar. As you take time to acclimatize you'll visit monasteries and other landmarks. When you're ready for higher elevations you'll be treated to the stunning views of Mt. Everest and Lhotse. Some treks go on as far as the Mt. Everest base camp, which sets at 17,600 feet and is the staging area for expeditions to the 29,035-foot summit. But don't feel any lesser for turning tail at the base camp, there are many other challenging summits you can reach without the extreme danger of the Everest ascent.
Pokhara is historically the cultural and commercial center of Nepal as the terminus of a major trading route with Tibet. The Pokhara region is very diverse and is known as a gateway to many types of outdoor adventures, including treks through the Annapurna circuit. Boating on Phewa lake is a great diversion along your route to tour the western Himalayan mountains.