A year of controversies over water-related projects like Thomas Heatherwick’s Garden Bridge in London, or Frank Gehry’s LA River master plan in Los Angeles, can paint a fraught portrait of the relationship between design and one of our most precious resources. But in honor of World Water Day, we have rounded up some of the projects that represent the most strategic, innovative, and unexpected intersections of design and H2O that have been featured on ArchDaily.

Architecture and water have a long history of intersection, from the aqueducts engineered by the Romans to Frank Lloyd Wright’s Fallingwater, and the relationship holds new value in an age of climate change coupled with evolving modes of thinking about the relationship between humans and ecology. An ever-broadening understanding of the human need for water—from health and hygiene to recreation and wonder—has ensured that new ways to incorporate this classic element into vanguard designs has flourished. The following projects feature water in a variety of ways, from proximity to bodies of water, to designs literally shaped or formed by their relationship to moisture, to projects that are physically immersed in the liquid, and finally other projects which are only visions of a yet-unbuilt future.

If there's one word that sums up our most popular projects of 2015, it's "diversity." The list features architects ranging from old favorites such as SANAA, Diller Scofidio + Renfro and OMA down to newer names like Sculp[IT] and Tropical Space; it also includes everything from museums to multi-family housing and spa retreats to chapels - along with the usual smattering of private residences. Interestingly, this year's list also shows the symbiosis between great architecture and great photography, with no less than 4 projects also appearing in our most bookmarked images from this year's World Photo Day. But despite their diversity, there's one thing all of these 20 projects have in common: great architecture. So settle in, relax and read on - here's our 20 most popular projects of 2015.

"Every picture tells a story" - at least, that's according to that great philosopher of our time, Rod Stewart. But what about the stories behind the pictures themselves? At ArchDaily we know that a great image requires not only great architecture but also a skilled photographer, so to celebrate World Photo Day we decided to find out more about the most popular images on ArchDaily. We've taken the ten most bookmarked images in My ArchDaily, and contacted some of the photographers to find out more about their images - read on to see the top ten, and to find out the stories behind six of them.