Bass Harbor Bar is a significant offshore shoal located at the southern entrance to Blue Hill Bay, near the southwestern tip of Mount Desert Island in Maine. It is marked by navigational aids, including a green can buoy at the harbor mouth and a red-and-white "WB" gong buoy a few hundred yards west of its shallowest part. The bar is a known hazard for small craft, as conditions can deteriorate rapidly. Paddlers report that even a light breeze can quickly create a confused sea with closely spaced three- to four-foot waves over the bar, particularly when wind opposes tidal flow. The area is exposed to winds from the south and east, creating a substantial fetch. Navigating across the bar requires careful attention to tides; at mid-tide, depths over the bar are approximately 45 to 50 feet, but the shallow water amplifies wave action. The primary safety consideration is the potential for rough, turbulent conditions that can arise quickly with wind and tide, making it an area recommended only for paddlers with advanced skills and solid seamanship. It is frequently advised not to paddle here solo due to these combined hazards of wind, waves, and potential fog. The bar is guarded by the operational Bass Harbor Head Lighthouse onshore. The surrounding waters see boat traffic, including the Maine state ferry to Swans Island and Frenchboro, lobster boats, and other power vessels, so paddlers must maintain situational awareness. A direct route from Bass Harbor Head to the nearby Gott Islands crosses directly over the bar, which is a common but potentially challenging passage. Paddlers are strongly advised to consult detailed marine charts and local guidebooks, such as the MITA Guidebook or "Sea Kayaking the Maine Coast," for specific advice on crossing conditions.