Dravo Corporation Shipyard. During World War II, Dravo's shipyard here was a leader in the manufacture of Landing Ship Tanks--LSTs--for the U.S. Navy. Dravo's over 16,000 workers produced a total of 145 LSTs. This and four other inland yards, all using techniques pioneered by Dravo, contributed two-thirds of the Navy's fleet of over 1,000 LSTs. These amphibious craft proved vital to the success of Allied landings on enemy shores, 1943-45.