They were very beautiful. There aren't many traffic laws, at least that are enforced. Other than that it is basically a free for all. Lanes are implied but not imperative. The most important thing is to get where you are going as fast as possible with the least injury to yourself or others.
Speed is essential.
Another critical thing is to warn everyone everywhere that you are one the way. This means liberal application of the horn. Horns are a constant sound in Kathmandu. They are simply a part of life. If you do not use your horn, you will not get anywhere.