The Kathmandu Valley is a region of 230 sq.miles (600 sq. km.) in the the Bagmati zone in central Nepal, and is home to three of the largest cities in Nepal, including Kathmandu itself, as well as hundreds of smaller towns and villages.
Boudhanath-(Boudha) Largest Buddhist Stupa in Tibet, a very important place of pilgrimage & meditation for Tibetan Buddhists, local Nepalis, & tourists. Dozens of Buddhist Monasteries/nunneries are in the area.
Bhaktapur -City of Devotees. No motorized vehicles in the city. Walk or ride bicycles only.
Chobhar - Ancient hill village, origins from the 12th century.
Daksinkali - Holy river gorge and site of weekly animal sacrifices. Hindu temple complex south of Kathmandu on the Bagmati River where it enters a gorge through the Mahabharat Range
Dhulikhel - Small town 30km south-east of Kathmandu in the heart of small hills and green valleys - perfect startpoint for short hikes. Try a 3-hours walk to the hill-top monastery of Namobuddha Monastery.
Lots of travel agents who can help plan iteneraries
Bring your manners with you. Tip those who serve you generously. Don't take people's pictures without their permission.
Meditation and/or yoga plenty of classes in many areas - see below, also look for notices or ask around.
A few words of Nepali "Don Knee Batt" = thank you. They say "Namaste" as a greeting or farewell - no more than once a day. A not watered down translation: the divine in me, recognizes the divine in you.
Rangjung Yeshe Institute, . An international institute for Buddhist higher studies in Baudha - modeled on a traditional Tibetan Buddhist College. The Institute is affiliated with Kathmandu University, and located on the premises of the monastery Ka-Nying [short for "Kagyu and Nyingma"] Shedrup Ling. It offers bachelors and masters degrees in Buddhist Studies with Himalayan Language (Tibetan, Nepali, and Sanskrit), as well as six week stand alone intensive courses in each.
Kopan Monastery, . Founded by Lama Yeshe and Lama Zopa as the core of what has become an international network of Gelugpa dharma centers, the Foundation for the Preservation of the Mahayana Tradition (FPMT). Located near Baudha, Kopan offers ten-day meditation courses regularly throughout the year, and a month-long course (for which it is famous) every November-to-December. Reservations are necessary.
Nepal Vipassana Centers, . Vipassana Meditation (a popular Buddhist Meditation) as taught by S. N. Goenka.
Bikram Yoga College of India,  Daily hot yoga classes in the heart of Thamel on a drop-in or monthly basis.
Patanjali Yoga Center, . The first residential school of Yoga in Nepal.
Satyananda Yoga Centre, . Group and individual courses. Yoga Camps.
The Healing Hands Center, . Classes in Ancient Massage / Thai Massage. Five-day course, ten-day course and one-month professional course, runs every month and recognized by THAI (Thai Healing Alliance International) worldwide and Natural Health Practitioners of Canada (NHPC).
TU Central Library, . It is one of the largest library of Nepal situated within Tribhuvan University premise at Kirtipur. You can get there by regular bus or micro-bus for Kirtipur. It has a large collection of old and new books, journals and newspaper.
British Council Library It is in Lainchaur beside British Embassy.
KEEP Kathmandu Environmental Education Project have a center in Kathmandu (behind Kilroy's), which provides environmental information about Nepal. They provide books for trekkers to record their experiences in for others to read before they set off. You can ask to see a BBC film entitled "Bearing the Burden" about Nepalese porters. They also provide a water bottle refill service that is also cheaper than buying new bottles (Rs 10). You can also buy there some biodegradable soap and iodine for your trek.