The project to locate the spot where the Endurance went under the Antarctic ice seemed simple and straightforward enough with all that modern technology at its disposal. They have a robotic submarine. But back then and as it is now, Mother Nature is not to be underestimated.
The UK-led expedition to the Weddell Sea sent a sub to the ocean floor to look for the sunken polar yacht, but this robot was itself lost in the process.
The team has now withdrawn from the area because of deteriorating weather and sea-ice conditions. The fact that Ernest Shackleton managed to survive and keep every member of his team alive under such vile conditions for nearly years makes this man a legend.