You're going to Lanzhou as a tourist?!?!

The most outstanding feature is the pollution - it's a long, thin city with mountains on either side which doesn't do much for the air quality.

In terms of attractions it doesn't boast much. Maybe you should try Tianshui instead - much nicer and plenty of things to see, albeit cold in December.

I'm not that well up on the restaurant scene there - but it's big enough that you'll have no problems finding excellent Chinese food. If you want non-Chinese you'll struggle to find anything decent.

PM with your dates - I get there every couple of weeks so a beer may be in order.