In 2025, Miami sank 22 concrete cars beneath the Atlantic; what looks like an underwater traffic jam is actually a giant artificial reef for 2,200 corals

Imagine looking down into the ocean and finding a line of cars sitting on the seafloor. That is exactly what visitors can see off Miami Beach, where 22 giant concrete car sculptures were installed underwater as part of an unusual mix of public art, coral restoration and climate resilience.

The underwater installation is part of REEFLINE, a project designed to turn an area of seabed into an artificial reef while creating a completely different experience for snorkellers and divers. The concrete vehicles are not abandoned cars. They were deliberately designed, prepared and lowered into the Atlantic to provide surfaces where marine organisms and restored corals can grow.

Why did Miami Beach put concrete cars underwater?

The unusual underwater traffic jam was designed by Argentine artist Leandro Erlich. The cars were placed about 20 feet below the surface in a line resembling the traffic congestion that is a familiar sight across South Florida.


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As per a TOI report, Ximena Caminos, founder and artistic director of REEFLINE, said the installation was designed to transform a symbol associated with environmental harm into a structure that could support marine life.

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“To me it’s a symbol from transportation to transformation,” Caminos said, according to the Miami Herald. She explained that transportation has contributed to environmental damage, while the underwater installation could transform that idea into a platform for corals and marine organisms.

The project therefore combines a fairly strange-looking art installation with a serious environmental purpose.

2,200 corals were placed on the underwater cars

The concrete cars were designed to provide a surface for marine life to colonise. Their hoods contain specially designed plugs where corals grown at the Miami Native Coral Lab in Allapattah were attached.

Around 2,200 corals were planned for the installation, with the restored corals adding shades of purple, green and yellow to the otherwise grey concrete sculptures.

Some of the corals have branching structures, while others have softer, feather-like forms. Over time, the artificial structures are expected to become increasingly integrated with the surrounding marine ecosystem.

Underwater traffic jam doubles as a coral research site

REEFLINE is not just about creating an unusual attraction for visitors. The site is also intended to give scientists another place to study coral restoration.

Researchers involved with the Rescue a Reef programme planned to use the sculptures to test different coral species and restoration approaches.

“We want this to be a playground for scientists to come and test their coral,” Caminos said, according to the Miami Herald.

The location was chosen because the sandy seabed was once associated with a more productive reef environment. Previous dredging activity contributed to changes in the area, and the project aims to create new habitat where marine organisms can establish themselves.

How can an artificial reef help Miami Beach?

Coral reefs are more than underwater ecosystems. Healthy reefs can also act as natural barriers by absorbing and breaking up wave energy before it reaches the shoreline.

That matters in Miami Beach, a barrier island exposed to storms, waves and coastal erosion.

The concrete sculptures were tested in the University of Miami's wind-wave-storm tank to assess how they would respond to strong ocean conditions. Their design was intended to withstand the forces they could encounter underwater.

Miami Beach Mayor Steven Meiner described the project as more than an art installation.

“The REEFLINE installation is more than a stunning fusion of art and science; it’s a critical long-term economic safeguard for Miami Beach,” he said in a press release.

How were the 22 concrete cars placed underwater?

Getting a fleet of concrete cars onto the seabed was a surprisingly complicated operation.

Before the installation began, divers marked GPS positions on the ocean floor so each sculpture could be placed in the planned location. The cars were then transported on a 160-foot construction barge equipped with a large crane.

The crane lowered the heavy sculptures into the water, while commercial divers guided them towards their final positions on the seabed.

Weather and sea conditions made the process even more challenging. Only one car could be installed on the first day because rough seas made it difficult to operate the crane safely.

Construction manager John Kearns explained why even small movements on the surface could become significant underwater.

“A six-inch shift on the surface means about three feet of movement underwater,” Kearns said.

After each sculpture was placed, the team also had to allow the surrounding seabed to settle before the site could be considered ready.

What is the future of the REEFLINE project?

The 22-car installation is only part of the larger REEFLINE vision. The project is planned as a much bigger underwater public art and artificial reef attraction, with additional sculptures proposed for the future.

Ideas include installations inspired by sea stars and the heart of a blue whale.

Miami Beach provided $5 million in funding for the project, while REEFLINE has also been seeking additional funding to expand the underwater installation.

For now, though, the concrete traffic jam offers a pretty unusual sight: cars that once symbolised road traffic are sitting beneath the waves, gradually becoming part of an underwater habitat for corals and marine life.


Inputs from TOI