They have several grills next to all of the picnic pavilions, so, I would assume the answer is yes. I would suggest checking the website or calling Upper Moreland township Parks & Rec department and asking about the permit to grill there. People do reserve the pavilions especially for large gatherings.
No grill at all at Masons Mill Park.
I would like to be able to answer your question but really not sure, check township website and park one.
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