Well, that depends on how the information is presented. If the information is being presented by someone who has experienced the event in question, that could be used as evidence. Direct observation could also be used as evidence. Studies use direct observation to determine a conclusion or to find an answer to a problem. The answer to your question is, both could be used as evidence.
Direct observation. This is because the anecdotal fallacy is a logical fallacy and says that isolated events are not adequate pieces of evidence. It must be a well-documented case to be evidence.
Bank Vaults as stated in Alan Weisman's book "The world without us" when he tries to depict the New York city scenery long after humans have disappeared from the earth.
