A breathtaking stalwart of the Milan skyline, the Duomo’s history spans more than six centuries of worship. The cathedral’s construction began back in 1386 at the peak of Gothic design, but was not truly completed until the mid-20th century. Over the decades, a succession of Italy's greatest architects, engineers and artists worked on the magnificent structure. Even Leonardo Da Vinci sketched some designs for a proposed domed tower, though they never made it off his drawing board.

It’s not the tallest building in New York City, nor is it the most famous, but the Flatiron building in Manhattan is definitely among the city's most striking. A triangular, 22-storey office block that looks almost two-dimensional when viewed from the side, the building was constructed in the Beaux-Arts style and measures just six feet (2m) across at its narrower end.

Dedicated to his late wife, Shah Jahan’s Taj Mahal is beautiful not only for its mesmerising marble facade. Their love story is one of bittersweet tragedy: Mumtaz Mahal ('the Jewel of the Palace') died while giving birth to their 14th child, so the emperor vowed never to marry again and promised he would build her the finest mausoleum ever seen.

Designed by famous Canadian-American architect Frank Gehry, the Guggenheim Bilbao is an artwork in its own right. The sculpture-like structure boasts titanium-clad curves designed to catch the light in different ways as the day progresses, and has been continually hailed as one of the greatest buildings of our time.

Often dubbed 'the world's only seven-star hotel' (erroneously, as official rankings stop at five), the Burj Al Arab is one of Dubai’s most iconic structures, and goes a long way to earning its nickname. Resembling a billowing ship's sail, it stands proudly just off the Dubai shoreline and is best seen from Jumeirah Beach at sunset, when the skies turn all shades of pink and orange.

Beauty is, famously, in the eye of the beholder, but few would deny that these stunning architectural marvels rank among the world's most attractive structures. From opulent palaces and soaring modern skyscrapers to fairy-tale castles, it's no surprise that these spectacular buildings draw thousands of tourists every year.

One of the world’s most precariously placed monasteries, Paro Taktsang (better known as the Tiger’s Nest) perches tentatively on a cliffside in the upper Paro valley in Bhutan. The elegant structure is built around a cave in the cliff face that is said to have been used by Guru Padmasambhava for meditation in the 8th century. Legend has it that he flew to the cave on the back of a female tiger.

Still under construction – it's finally slated for completion in 2026 – Gaudi’s most celebrated work nevertheless draws millions of visitors to experience its grandeur every year. The elaborate building’s most impressive part is its dramatic Nativity facade, which was created under the personal supervision of Gaudi himself and boasts thousands of intricate carvings related to the birth of Christ.

Office of Coast Survey products and services have an inherently international dimension. Beginning with an Act signed in 1807 by President Thomas Jefferson, Coast Survey became the nation's chartmaker in 1832. More than 200 years later, the U.S. depends upon maritime trade and economic activity associated with the use of coastal waters and resources. This trade supports the 1.3 billion metric tons of cargo valued at $1.8 trillion coming in and out of U.S. ports every year. The Coast Survey International Program and Plan builds upon Coast Survey's core strengths, capacities, and directions as a global leader in hydrography.

Reefs in the Indo-Pacific region, like this reef in Australia, have greater coral species diversity than their counterparts in the Atlantic/Caribbean. Photo credit: Dave Burdick
Conserving the nation's coral reefs cannot be accomplished by domestic efforts alone. Our coral reefs are ecologically connected to those abroad. Additionally, the most significant threats they face—climate change and ocean acidification—are global in nature.

Effectively conserving coral reefs and the services they provide depends upon sound ecosystem-based management practices and good governance—from local communities to multinational regions. Together with our partners, we work in more than 40 countries and multilateral regions globally, with particular focus in the Coral Triangle, Micronesia, the South Pacific, and the wider Caribbean