Where are the only significant shoals, which are dangerous to navigation, located on Lake Ontario?

The significant shoals that pose dangers to navigation on Lake Ontario are primarily found at the northeast end of the lake. This area is characterized by shallow water and underwater hazards that can be treacherous for boats and other vessels if not navigated with caution. Shoals can significantly affect the depth of the water, making it difficult for larger vessels to pass safely and increasing the risk of grounding. Knowledge of this geographical feature is crucial for safe navigation, especially for those operating in the region.

Other areas of the lake may have shoals, but they are not considered significant in terms of danger. Each end of the lake has its own navigational challenges; however, the northeast end is particularly noted for these hazards, reinforcing the importance of local knowledge and navigation charts when traveling in these waters.