Unfortunately, China being what it is, unless you're willing to spend the money for a plane ticket, most train rides will be quite long. Try to book plane tickets real early if you can.

As for travel destinations for the summer, my advice would be to avoid the obvious spots - Hunan, Yunan, Xi'an and the rest. They're usually massively packed with people.

If you're brave enough to stand the heat, Xinjiang is really worth it, as are the neighboring provinces.

If you want a more relaxed destination, I personally loved Fujian province: Xiamen has got to be the most comfortable (and cleanest) city in China.

Next to Suzhou, there's this sublime old city called Tongli, with just a few thousand habitants, which is also quite unbelievable.

There are really loads of destinations. Thing to keep in mind, unfortunately, is that you'll most likely have to travel by plane to get there.

You didnt mention how long you have to travel?

The whole of China is very hot in the summer as you are aware of already Beijing is already 34C. I 2nd the vote for Fujian and Xiamen, but I also fell in love with Yunnan when I lived there, especially the Dali-Lijiang-Zhongdian area (the only place in China you can avoid the heat of summer). I think Guangxi Guiln-Yangshuo is worth a few days.

Long train-bus rides are the only way to keep travel on the cheap.. If you make it to Xiamen send me a PM, I run a hostel here in the old town...

xiamen,harbin , hainan

Emei shan

I would go to Sichuan or Yunnan this summer. Both areas can be pleasantly cool compared to the rest of the scorching country, especially if you go to the higher altitude areas such as the area bordering on Tibet in Sichuan (Kangding etc.) or going to the foothills of the Himalayas in Yunnan. If you fly to these places you can get their in a couple of hours. However, trains to Yunnan are extremely slow.