a lake and 14 footers
I am presuming you're referring to what we call the 14ers out here...the mountains over 14,000 feet. Well, there are 58 of them at last count, which changes sometimes when new ones come on board.
One of the best places to have lakes/rivers and 14ers would be the Arkansas River Valley. LOTS to see and do in that general area, in which I would also include the Taylor Park area west of Cottonwood Pass.
Lakes/Rivers and the northernmost 14er (Longs Peak) in the area in and around Rocky Mountain National park, to include the Big Thompson Canyon, the Poudre Canyon, Red Feather Lakes, the Grand County area of Granby/Grand Lake/Fraser/Winter Park and the North Park area around Walden.
These are just 2 of many considerations.