Most slaves endured the harsh routine of plantation life. Because of their concentration on large plantations, within these constraints they built their own culture, often developing leaders through religion, and others who acquired particular skills. They created their own religious practices and worshipped sometimes in private, developing their own style of Christianity and deciding which stories, such as the Exodus, spoke most to them. While slave marriages were not legally recognized, many families formed unions that lasted, and they struggled to maintain their stability. Some slaves with special skills attained a quasi-free status, being leased out to work on riverboats or in the port cities. Those on the riverboats got to travel to other cities; they were part of a wide information network among slaves.