by site editor Rick McCharles
Updated from my original 2010 post.
This post is for anyone considering a future hiking adventure in Nepal.
Where is the best hike?

If you simply want to sign on with a Trekking Company, start at Exodus U.K., one of the most respected firms.
For example, Mount Everest Base Camp is offered by Exodus at about $150 / day. Or more.
There are hundreds of other Trekking Companies, hundreds of other guided itineraries to consider. Some very cool options.
… However, besthike.com exists (mainly) for the independent trekker. Those who want to organize their own hike, normally carrying their own gear.
Everest Base Camp independently will cost you about $15 / day plus transport. Perhaps 10% of what you would spend with Exodus.
Your best starting point for researching an independent hike is Lonely Planet Trekking in the Nepal Himalaya 9th edition (August 1, 2009).

Almost all independent hikers go to these destinations:
1) Everest
2) Annapurna
3) Langtang
My advice is that first time hikers to Nepal should go to Everest. Second best is Annapurna. Last choice, though still excellent, Langtang.
Everest is wonderful. Iconic. Easy to organize. And is reasonably safe as you have plenty of time to acclimatize before reaching Base Camp.
Annapurna was formerly our favourite destination. But the experience has been degraded by road construction — is the Annapurna Circuit dead?
Once you’ve decided on the destination, here’s our advice for best hike for independent trekkers:
1) Annapurna – Annapurna Circuit 21 days
2) Everest – Three Passes 20 days
3) Langtang – … various options 5-15 days
If you insist on going with a guide, consider the trip fastest gaining popularity, the Manaslu Circuit, near Annapurna. Guides are mandatory on Manaslu.
If you are short on time, go to Langtang. It’s close to Kathmandu. Easy and inexpensive to organize.
I did 16 days in both Annapurna and Everest by pushing some long hiking days. That’s minimum, I’d say. I wish I’d had more days on both trips.
You really don’t need a guide in any of these 3 highly developed destinations, but you may want to hire a guide and/or porter(s) to enhance your holiday. My advice is to do that as you go in the villages of Nepal. Almost any Guest House can arrange those for you with just a few hours notice. This way all your money goes directly to the local people. (You might want to hire a porter just for a day or two, for example.)
Recall that you can carry a very light pack in Nepal. Sleeping bag, clothing and personal essentials are all you need. And a stack of Nepali Rupees, of course, to pay for your bed and meals each day.

I saw independent hikers at Everest Base Camp who had never before done an overnight hike. (Tolerance for smelly, freezing pit toilets is the main “talent” required. Not high altitude trekking experience.)
Leave a comment if you have any advice to add.
Or if you have any specific questions.