How London's 'iceberg' homes and luxury mega basements represent wealth burrowing underground - ABC News
Basement Design Studio | Buying next to someone planning an “iceberg basement”?
Iceberg Homes, the Underground Mansions of London Billionaires
Iceberg homes: That's what today's billionaires are building - with underground discos, dog spas and even waterfalls... but it's driving the neighbours crazy | Daily Mail Online