Gently sloping rock surface found at the foot of a coastal cliff. Covered by water at high tide but exposed at low tide, it represents the last remnant of an eroded headland (see coastal erosion). Wave-cut platforms have a gentle gradient (usually less than 1°) and can be up to about 1 km/0.6 mi in length. Over time, wave-cut platforms are lengthened and protect the cliffs behind them.
The emblem reflects the Vatican's importance as the headquarters of the Roman Catholic Church. The colours of the flag are based on the gold and silver of the papal keys. Effective date: 8 June 1929.