Where in Thailand should I stay?

This is the route I took around Thailand:

http://luckytravelblog.wordpress.com/2013/09/16/th...

This took me a month, I am not sure on how long you are planning to go.

Koh Tao is supposedly the cheapest place in the world to learn to Scuba Dive, and it is beautiful!:

Visit Chiang Mai for culture and some great temples; also a fantastic place to ride elephants! If you plan to visit Chiang Mai definitely take a few days to visit Pai; it is one of the most chilled out places in Thailand and has some great things to see.

There are two places you should look at for scuba diving. One has been mentioned Koh Tao the other is Similan Islands on the west coast of Thailand south of Ranong. But you need to check the weather at which time of the year you are going. Fall season where you are could be different in another part of the world.

As for culture, it's everywhere in Thailand not just up north or northwest but any small rural town or village you will find Thai culture. There are many beautiful temples and historical sites spreed out all over the country. Doing your research find the ones most interested in the areas you plan to travel.

Scuba at beaches.

Most famous native culture is way up North Thailand beyond Chand Rai.

Chang Mai is the most boring place I have been in Thailand.... parts look like Westwood, LA, Calif.

If they fix the tracks by your time here, I recommend the overnight sleeper train.

SCUBA dive. It has to be Koh Tao, it has some of the best reefs in easy reach of the island and many dive operators.

As for the culture, pick a place, I like chaing mai.

Culture and nature Chiang Rai, Chiang Mai, Isan and sorroundings.

Diving and sea nature in Koh Tao, Koh Chiang, Koh Kradan.

Good answers. Also pick up Lonely Planet guide book for Thailand.

Enjoy your stay.