The Stelling van Amsterdam was the most advanced military structure of its type in the world – 135 km (84 miles) of forts, batteries and moats completely encircling the city in a defensive barrier.
The Outer Trial Bank is a circular artificial island in the Wash, East Anglia, England. It is one of two islands constructed during the 1970s for a governmental water resources scheme.
A bridge which connects Hong Kong with Macau and Zhuhai, is the world’s longest sea crossing.
Snake Island is one of the deadliest and most restricted places on earth. The island lies off the coats of Brazil and is home to at least 4000 species of the world’s most venomous snakes alleged to possess the ability of melting human flesh. The island is banned to tourists and is only open to scientists for study and research.
In 1948, a top-secret biological weapons laboratory, nicknamed Aralsk-7, was established here. Until its closure in the 1990s, the laboratory tested some of the deadliest pathogens known to man, including plague, anthrax, smallpox, brucellosis, tularemia, botulinum and Venezuelan equine encephalitis.
The stunning tropical islands of Maldives, southwest of India, is known for its sandy beaches and turquoise waters. But very few are aware of its dirty side.
The island town of Suakin, in north-eastern Sudan, was an important port for trade and culture on the East African coast for centuries.