Driving on the Long Sault Parkway is free, but it costs $7.25 to buy a day pass to park at any parking lot or visit the beaches. The scenic drive is 11 km long on a chain of causeways and bridges that connect a dozen islands on the St. Lawrence River.
The Mille Roches Beach is larger than the Woodlands Beach so there’s a lower chance of getting turned away there. Macdonell Island has a manicured green knoll along the southern shore facing the US, it’s the perfect place for a break and a picnic.
I would highly recommend you park your car at the beach to enjoy a barbecue before cycling the full length of the parkway.