"Most of the ones I looked at had just cracks in the wall--of no structural significance, " he says.

CNN: ASIANOW - TIME Asia | Taiwan: The Day the Earth Moved--Page 3

Using state-of-the-art surveying equipment, Reeves is expected to begin searching cracks on the northern wall for a secret doorway leading to a previously undiscovered space.

CNN: Search for Nefertiti's burial site given green light

Deep cracks beneath the waterline led to parts of the 80-year-old harbour wall collapsing in 2012.

BBC: Weymouth harbour wall: Warning over repair noise