Parkwood Estate on Simcoe St. in Oshawa is always a beautiful location for photos only or as a Wedding Venue.
There is a ton of good park space in Ajax down near the waterfront, here's a link to the town of Ajax site for some ideas :)
Depending on how far you want to drive there's also Greenwood Conservation area or there is a barn site up near Deer Creek Golf Course that some photographers go to sometimes (My sister had her pictures for her wedding done there).
The Waterfront is probably your best bet though cause it's closer to the Hilton Garden Inn. There's supposed to be a wildflower meadow in the waterfront parks too.
Hope I helped a little :)
thank you so much! :)
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