The North Atlantic island of Bermuda has no freshwater springs, rivers, or lakes. So how did humans ever settle there? The secret is in the design of their houses, and particularly the white stepped roof, which is still in use 400 years after it was first introduced.⁠ Visitors to Bermuda will feel instantly at home, even if the weather is far warmer and sunnier than anything imaginable on the British Isles. ⁠ ⁠ Many of the island's 60,000 residents live in limestone cottages painted in pastel colors of a design familiar from British towns or villages. It turns out that white roofs are designed this way to harvest rain. The steps slow down heavy rainfall, helping the gutters to collect the water and store it in a tank under the house.⁠ ⁠ _____⁠ ⁠ Thanks partly to an annual rainfall that far exceeds that of England and Wales, and is spread fairly evenly throughout the year, the tanks are regularly topped up. Each home is self-sufficient. There is no mains water - and no water rates.⁠ Thi...