Are there jumping rocks at Halfway Lake, and how far is Chelmsford from Halfway Lake? Is there a grocery store nearby outside the park?
The nearest store is a QuickMart in Onaping about 45km south on Hwy 144.
There is the small town of Cartier between the park and Dowling but I don't know there is a store there anymore.
There is a Valumart at Dowling another 5km down 144 both are small town stores with small town hours - check out their websites. After that Chelmsford is about another 10k so 55km from the park where you'll find pretty much everything you need.
I'm not sure what you mean by jumping rocks so I can't answer that part of your question.
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