On 17 December 1914, Curie, at the insistence of her French-Irish commander Gabriel O'Byrne, departed her base in the Ionian Sea under tow by the French armored cruiser Jules Michelet.[5] Depositing her charge 150 nautical miles (280 km; 170 mi) from Pola,[5] the site of the Austro-Hungarian Navy's main base,[3] Jules Michelet departed, leaving Curie to proceed to the Austro-Hungarian base. Curie arrived the next day and began reconnoitering the entrance to the harbor. O'Byrne observed the entrance and exit paths of Austro-Hungarian vessels and plotted a course through the deployed defensive mines.