Imagine the architect responsible for such momentous projects as the new Whitney Museum, The Shard in London, and reunified Berlin's Potsdamer Platz, on his hands and knees on a sandy beach. Imagine him digging a trench and piling buckets of wet sand into a mound with concerted precision, only to start laughing and cavorting like a child as the tide comes in and his work is destroyed. Then doing it all over again.

He may be on to something: as quoted in The Guardian, he explains matter-of-factly, "I have four children; the oldest is 50 and the youngest 16, so I have been making sandcastles for a long time. There is no age limit – you can enjoy making a sandcastle however old you are, although it helps to think like a child."

His method for sandcastle building is at times very precise (the angle of the sand mound's incline should ideally be 45°) and decidedly whimsical: "The magic moment is when the waves come and the ditch becomes a moat ... To capture the image in your memory quickly, close your eyes when the water comes in."

But the most important thing when it comes to sandcastles is location: "A sandcastle’s relationship to water is more important than its appearance. Study the waves, then decide where to position your castle – too low on the shoreline and the sea will immediately destroy it, too high and you have no waves to flirt with. It sounds complicated but it’s simple and instinctive."