Nepal has the best trekking areas in the world and several of the world's highest mountains, including Mount Everest. Many people visit the country just to trek and the tourism industry is well prepared to facilitate all types of trekking styles and destinations. On the one hand, you could spend a year planning an expedition to wild and lofty places; on the other, you could land in Kathmandu with no plans and be on the trail to Everest Base Camp (EBC) in a matter of days.
Only TAAN registered trekking agencies in Kathmandu and Pokhara can legally organize treks and provide the services of a guide and/or porter with insurance. Be aware that no one else, no hotel, no street broker, no nice person you just met, not even a trekking guide is legally authorized to organize a trek. During the main seasons, the agencies run regular group treks, both tea-house, and camping styles, and it is generally possible to join a group doing a trek of your choice. Independent trekking is quite easy in the main trekking areas. Required Permits a trekking permit issued by the Department of Immigration is required to trek in any part of Nepal, except the most popular areas of Annapurna, Khumbu, and Langtang/Helambu.