For 10 points, name this middle of the Prairie Provinces whose largest city is Saskatoon.
This polity's largest naturally occuring lake that is contained entirely within it is Long Lake, although the construction of the Qu'Apelle River Dam and Gardiner Dam created its largest man-made reservoir, Lake Diefenbaker. The capital of this province is situated nearby Wascana Creek. Smaller lakes within this geographical unit include Cree Lake and Reindeer Lake. Cities within this polity include Yorkton, Swift Current and Moose Jaw.  The Mosaic Stadium within Taylor Field can be found at this province's second largest city. The namesake of this province is a river that eventually dumps into Manitoba's Lake Winnipeg. For 10 points, name this middle of the Prairie Provinces whose largest city is Saskatoon.
This polity's largest naturally occuring lake that is contained entirely within it is Long Lake, although the construction of the Qu'Apelle River Dam and Gardiner Dam created its largest man-made reservoir, Lake Diefenbaker.
Saskatchewan