SM U-1 or U-I was the lead boat of the U-1-class of submarines or U-boats built for and operated by the Austro-Hungarian Navy (German: kaiserliche und königliche Kriegsmarine or k.u.k. Kriegsmarine). U-1 was designed by American naval architect Simon Lake of the Lake Torpedo Boat Company, and constructed at the Navy Yard in Pola. She was one of two Lake-designed submarines purchased as part of a competitive evaluation of foreign submarine designs after domestic proposals were rejected by the Navy.