High Quality Content by WIKIPEDIA articles! The blockade runners of the American Civil War were seagoing steam ships that were used to make their way through the Union blockade that extended some 3,500 miles along the Atlantic and Gulf of Mexico coastlines and the lower Mississippi River. To get through the blockade these ships had to cruise by undetected, usually at night. If spotted the runners would then attempt to outmaneuver or simply outrun any Union ships on blockade patrol. The typical blockade runners were privately owned vessels often operating with a letter of marque issued by the Confederate States. These vessels would carry cargoes to and from neutral ports often located in Nassau and Cuba where neutral merchant ships in turn carried these cargoes, usually coming from or destined to England or other points abroad. Inbound ships usually brought badly needed supplies and mail to the Confederacy while outbound ships often exported cotton, tobacco and other goods for trade and revenue while also carrying important mail and correspondence to suppliers and other interested parties in Europe, most often in England. Some blockade runners made many successful runs while many others were either captured or destroyed. Estimates vary somewhat among historians but almost all indicate that approximately 2500-2900 attempts were made to run the blockade with at least an 80% success rate. By the end of the Civil War the Union Navy had captured more than 1,100 blockade runners and had destroyed or run aground another 355 vessels.