lhdiver wrote:
A good zoom such as 18-300 or 28-300 is a good choice as there are many subjects both near & far that you will want to capture. You don't want to carry more than you need or change lenses more than necessary since you will be in crowds & it can be hot & dusty.
I echo IHdiver's comments. I went to India and Nepal about two years ago. A great trip with lot's of photo opportunities of temples, brightly colored dress and markets. I primarily used a 18-300 lens, which I found very useful when taking discrete photos of people and events.