The Bruce Peninsula Grotto is a natural sea cave located on the Georgian Bay shoreline in Bruce Peninsula National Park, Ontario, Canada. The Grotto is a popular destination for hiking and swimming, attracting thousands of visitors every year. The cave itself is carved into the Niagara Escarpment, a limestone ridge that runs along the length of the peninsula, and is filled with crystal-clear turquoise water that is perfect for swimming and diving.

Access to the Grotto is via a hiking trail from the main parking lot in Bruce Peninsula National Park. The trail leads through the forest and along the shoreline of Georgian Bay, and visitors will encounter stunning views of the lake and surrounding cliffs along the way. The Grotto is located at the end of the trail and visitors can access it by climbing down a set of steep stairs.

The Grotto is open year-round, but swimming is only recommended during the summer months when the water is warm enough. Visitors are encouraged to bring sturdy footwear for the hike to the Grotto, and to be prepared for potentially long wait times to access the cave during peak season. The Bruce Peninsula Grotto is a beautiful natural wonder and a must-see destination for anyone visiting the Bruce Peninsula region.