On July 29, 1966, Bob Dylan suffered injuries due to a motorcycle accident. Or at least we think he did. It's one of the most mysterious incidents in the history of rock and roll, one where it's hard to separate what likely happened from the myths that have grown up around it. We might never know the true answer. But if we go back to when it happened and examine the circumstances, we can take our best educated guess about what essentially put an end Bob Dylan's most furiously productive era.