Late on April 16, 1961, the CIA/Brigade 2506 invasion fleet converged on 'Rendezvous Point Zulu', about 65 kilometres (40 mi) south of Cuba, having sailed from Puerto Cabezas in Nicaragua where they had been loaded with troops and other materiel, after loading arms and supplies at New Orleans. The US Navy operation was code-named Bumpy Road, having been changed from Crosspatch on 1 April 1961. The fleet, labelled the 'Cuban Expeditionary Force' (CEF), included five 2,400-ton (empty weight) freighter ships chartered by the CIA from the Garcia Line, and subsequently outfitted with anti-aircraft guns. Four of the freighters, Houston (code name Aguja), Río Escondido (code name Ballena), Caribe (code name Sardina), and Atlántico (code-name Tiburón), were planned to transport about 1,400 troops in seven battalions of troops and armaments near to the invasion beaches. The fifth freighter, Lake Charles, was loaded with follow-up supplies and some Operation 40 infiltration personnel. The freighters sailed under Liberian ensigns. Accompanying them were two LCIs (Landing Craft Infantry) 'purchased' from Zapata Corporation then outfitted with heavy armament at Key West, then exercises and training at Vieques Island. The LCIs were Blagar (code-name Marsopa) and Barbara J (code-name Barracuda), sailing under Nicaraguan ensigns.
The CEF ships were individually escorted (outside visual range) to Point Zulu by US Navy destroyers USS Bache, USS Beale, USS Conway, USS Cony, USS Eaton, USS Murray, USS Waller. A task force had already assembled off the Cayman Islands, including aircraft carrier USS Essex with task force commander John A. Clark (Admiral) onboard, helicopter assault carrier USS Boxer, destroyers USS Hank, USS John W. Weeks, USS Purdy, USS Wren, and submarines USS Cobbler and USS Threadfin. Command and control ship USS Northampton and carrier USS Shangri-La were also reportedly active in the Caribbean at the time. USS San Marcos was a Landing Ship Dock that carried three LCUs (Landing Craft Utility) and four LCVPs (Landing Craft, Vehicles, Personnel). San Marcos had sailed from Vieques Island. At Point Zulu, the seven CEF ships sailed north without the USN escorts, except for San Marcos that continued until the seven landing craft were unloaded when just outside the 5 kilometres (3 mi) Cuban territorial limit.