Xībù Huānlèyuán (西部欢乐园) is a mini theme park in Xīgù District (西固区), west Lanzhou. There are fairground rides (carousel, pirate ship, and so on), a roller-coaster, swimming pool, golf driving range, and a 'panorama tower'. It's pretty-much closed down in the winter months, so head there on a summer weekend.

Location: Map
Getting there: From Anning, take buses #3, then #80 (route). From the city centre, take buses #26 or #127 (which departs from the train station, route)
Cost: Entrance to the park is free. There is a ticket office where you can buy books of tickets for the rides, or you can pay at the rides individually (Y5-30) 

More on Lanzhou's parks here and here.
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A new Parkson Department Store 百盛 (Bǎishèng) has opened on Qìngyáng Lù (庆阳路), a few hundred metres east of Nánguān Shízì (南关什字). Map. It's got 5 floors of all the usual department store sections, but the 3rd floor supermarket is quite high-end for Lanzhou: easily the best selection of imported wines, spirits, beers, ground coffee, tea and snacks in the city. It's not cheap (who's going to spend Y20 on a small bottle of mineral water?), but on the whole the prices are typical for these brands. No fresh produce or dairy. If you are into cooking western food, Bai'an is still the place to go. See here for more imported food and drinks.
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