Complex sentence: The tide used to go in and out under the building until at least the 1950s, but as of 2013 the beach has risen so that the piers are no longer visible and the sea has receded away from the Bandstand.
Split into simpler sentences: The tide used to go in and out under the building until at least the 1950s. As of 2013 the beach has risen so that the piers are no longer visible and the sea has receded away from the Bandstand.