A week ago I went with a few of my classmates to visit a mountain a few hours outside of Nanjing called Mao Mountain (Máoshān 茅山). We hired a tour guide (80 Yuan per day = $12.88) and toured the temples on the mountain for a few hours.
As we were leaving the tour guide asked if we wanted to see something mysterious. Of course, we said yes! She brought us to a memorial for the second Sino-Japanese War (1937-1945). The memorial was normal but when someone lit firecrackers at the bottom of the memorial something strange happened. Listen to the video below and see if you can hear the weird echo.
Did you hear it? The echo sounds like someone blowing a trumpet! The tour guide said that nobody knows what causes the strange echo. Supposedly, many professors from Nanjing University have visited the mountain and tried to solve the mystery but failed. The local people say that it is the ghost of a soldier whose job it was to blow his trumpet to call the soldiers to battle. Do you guys have any ideas? What could be happening scientifically to cause this strange echo?