A lot of Southport is built on sandbanks and much of the rest of it on reclaimed land. Some of the houses were built on 'rafts'. I used to remember a lot of houses that were at crazy angles where the foundations had slowly sunk into the marshland! The beach has changed a lot since they stopped doing so much dredging in the Ribble, so they have a tide that actually comes up to the sea wall nowadays!
Yes, it's on topic as it's where I come from too! Though I am in exile across the Pennines.