How was Troy really destroyed?

Could you elaborate on the true circumstances surrounding the downfall of Troy? What was the actual sequence of events that led to its devastation? Was it purely a result of the Greek's Trojan Horse strategy, or were there other contributing factors at play? Was there any internal strife or weaknesses within Troy that may have played a role in its downfall? How accurate are the stories and legends that have been passed down through the ages regarding the destruction of Troy?