Glacier Bay National Park, Wilderness and Preserve sits at the northern end of the Alaska Panhandle, on to the Alsek River, one of the state's 26 national wild and scenic rivers and a favorite of rafters. Glacier Bay's waters are arguably the finest sea-kayaking grounds in the world. There are hundreds of cubic miles of ice of the Brady Icefield. Rivers of ice, such as the Lamplugh and Grand Pacific Glaciers, stretch out with serrated ridges clearly hinting at their flow patterns. There are narrow fjords and bowl-like cirques which show how those immense ice flows carved them out of rock. Due to the heavy weight of hundreds of feet of ice and snow above, the bottom layers slowly start creeping forward and eventually break off or calve into the water ways, It is quite a sight to see this phenomena, specially in Glacier National Park, where the ship comes face to face (at a safe distance), with ice/snow cliffs over 100 feet tall. Glacier Bay National Park is a spectacular Park, surrounded on all sides by major Glaciers except the water way or the passage way that was carved out by the moving glaciers, which makes the cruise ships and other boats go to the middle of it all. The bay is about 65 miles long and anywhere from 2 to 10 miles wide. Only about 200 years ago, the ice was 5000 feet thick. The park includes 12 active tide water glaciers that calve into the bay on a regular basis.