Memories in the Brain

Human beings always tend to recall the past incidents in their lives to compare with the present events. Since birth, the events become memories and are lodged into the brain. In which manner do the memories lodge inside our brains ?. Are they stacked one over another like sedimentary seams ?

But that may not be the case because retrieval of the deepest buried memories shall be very difficult. Are they scattered in different places in the brain. This way retrieval may be easier. Brain might be the most complex structure to delineate although like most of our other body parts we least bother about how these all work.