Travelling Advice - Nepal/Tibet - The Himalayas

So I'm planning a holiday to the Himalayas and wanted to get some advice and information about it, hopefully from people who have already been there.

I have read that the best time to go is in October as the weather is best then. I will most likely be travelling alone but doing it with a tour group. I am looking to spend 2-3 weeks there. Money isn't an issue.

This one tickled my fancy:
www.lonelyplanet.com...

From the looks of things Nepal seems to have better scenary than Tibet - It looks more green whereas Tibet looks more like a wasteland. So most likely I would want to spend the majority of my time in and around Kathmandu. I don't plan on doing too much hiking I am going more for the spiritual/meditation side of it.

I would really like to hear what peoples suggestions are, what to expect, what to do, what to bring, etc.

I'm gonna do a trip like that 2 in 2015. If you're going for meditation you mos definitely have to stop by in Tibet and chill out with the monks there. While you're there ask them about Agartha and see how they react. There are rumors that there are secret tunnels in Tibet leading to the inner earth world known as Agartha. Have a wonderful trip !

I have never been there in Kathmandu, but heard much about the meditation possibilities available there. A number of Yoga centers and such institutions are there to offer some kind of peaceful moments. I'm sure it will be a great experience for you.