Putao is at the very north of Burma, in Kachinland. There are three airlines operating internal flights in Burma, two of which are private and generally get good reviews by travelers. The third one is government-owned and said to be unreliable: of course, that's the only one flying to Putao. Passengers tend to bring an amazing amount of luggage. From Mandalay, it's manufactured goods, and on the way back it's grapefruits, oranges and kumquat, which are famous products from the north. They load kilos of fruits, as hold luggage and also as hand luggage: so much that the aisle of the plane is filled up entirely (the hostess couldn't possibly walk to the rear of the aircraft!!). Monks and foreigners are granted the tremendous privilege to have a seat in the front row!
The Kachin are an independent-minded Tibeto-Burman people. They are famous for siding with the British in WW2, unlike the Burman of the plains who were pro-Japanese.
In the early 60s, Kachin followed the example of other hill people of Burma and took arms against the Yangon government. For years they ran their own territory, with their own schools, hospitals, mail service and churches (many Kachin converted to Christianity following the visit of missionary Ola Hanson at the end of the 19th century). The war only ended in 1994 with a cease-fire between the central government and the KIO. The Kachin were allowed to retain their weapons and administer the regions they had controlled. This explains why the Yangon regime won't let foreigners drive up to Putao. Only government controlled areas are opened to travelers.
Kachin is a Burmese word, designating a group of tribes: Jinghpaw, Maru, Lashi, Atsi, Lisu and Rawan. Each Kachin belongs to one of 5 original families: Marip, Maran, Lahpai, N'Hkum and La Haw. These clans are all inter-related. These complex family links give an amazing cohesion to the Kachin, despite their linguistic and tribal divisions.
There are about a million and a half Kachin in Burma, and about 120000 in China and 40000 in India.
The Khamti Shan on the pictures are not Kachin but Shan (i.e. related to the Thai). They wore their traditional dresses as they were on their way back from a celebration at a Buddhist pagoda (near Namkham, a small village on river Mali Hka, which when meeting Nmai Hka becomes river Ayeyarwadi -or Irrawaddy- . Note that this small Namkham should not be mistaken with the city Namkham).
The market in Putao takes place at 6am. That's a great place for noodle soup breakfast and sticky red rice (which you won't have finished digesting after 2 days and will enable you to run 4 marathons in a row). It's always cold and foggy at this time of the day, but by 10am the sun is usually back -at least in November-.
From Putao, you can see the first white peaks of the Himalaya. We only saw them from the plane, though, coz we always had those low clouds hiding them from us (except for a glimpse or two).

For further reading about the Kachin and Kachinland:
"The Kachin: lords of Burma's northern frontier" by Bertil Lintner, Teak House, ISBN 1-876437-05-7

"Among insurgents: walking through Burma" by Shelby Tucker, Flamingo, ISBN 0-00-712705-7.