Most of the world’s famous landmarks are very obviously the product of great architectural minds. Whether you’re looking up at the Eiffel Tower in France, the Taj Mahal in India, or the Burj Khalifa in the United Arab Emirates, you immediately get a sense of the depth of thought that must have gone into making such incredible structures.

Architecture can also be more subtle, with some human designs taking inspiration from natural features to deliver something equally striking. This guide will take you through some of the best attractions that tourists may not instantly realize are the work of human architects, from man-made water features to artificial islands.

Blue Lagoon – Grindavik, Iceland

Iceland is a nation renowned for its natural beauty, but one of its most popular and breath-taking tourist spots is actually a man-made construction. The Blue Lagoon appears to be a natural hot spring, but it was built because of runoff water from the nearby geothermal power station.

Its proximity to the Keflavik International Airport makes the lagoon easily accessible, with some tourists declaring that the calm blue water has skincare benefits. Whether that is true or not, you can’t deny the placid beauty of the Blue Lagoon.

Palm Jumeirah – Dubai, United Arab Emirates

Nakheel Properties’ tree-shaped design of the Palm Jumeirah island is one of Dubai’s most iconic architectural achievements, while the island is host to a string of top-class hotels. There are extravagant options for residents too; while there are plenty of villas for rent in Dubai as a whole, Palm Jumeirah is one of the most desirable luxury locations.

That's why the likes of David and Victoria Beckham have made a home in a villa on Palm Jumeirah. Residents have attractions like the Aquaventure Waterpark and the Lost Chambers Aquarium on their doorstep, while thrill-seekers can go skydiving over Palm Jumeirah to fully appreciate the shape of the artificial island.

Cheonggyecheon – Seoul, South Korea

This used to be a polluted creek flowing through Seoul, with an elevated highway running above. An ambitious 2003 project led by the mayor of Seoul, Lee Myung-bak, removed the highway and used an artificial pumping system to restore the Cheonggyecheon waterway.

This move reduced inner-city traffic, while the greenery alongside the renovated waterway now takes pedestrians on a more scenic route through Seoul. The visual appeal of the waterway has made this a must-visit for tourists in the South Korean capital.

Siloso Beach – Sentosa Island, Singapore

Siloso Beach is part of a 2 km stretch of beaches along the edge of this picturesque Singaporean island, with the Palawan and Tanjong beaches also the product of human design. These beaches use reclaimed sand, but an unwitting tourist would have no reason to question their authenticity.

Sentosa Island has plenty for tourists, from its golf courses to the Universal Studios Singapore theme park, but visitors must end up on one of the beaches at some point. Siloso Beach is famed for its beach volleyball and water sport facilities, so head there first if you’re a fan of sport.

Marmore Falls – Terni, Italy

The other attractions in this guide are largely the work of modern architects, but Marmore Falls is a little different; this is the biggest man-made waterfall in the world, and it was designed by the ancient Romans.

Located near Terni, the Marmore Falls are 165 meters of stunning cascading water. The Romans built this as a means to divert the water’s path, but tourists can now attend viewing platforms to watch the falls being turned on each day as part of a hydroelectric system.

If you’re planning a holiday in any of these countries, then it is definitely worth trying to incorporate these architectural achievements into your visit. The way that these attractions blur the line between the natural and the artificial is worth seeing with your own eyes