Aquariums may be as old as the Roman Empire, but large public aquariums didn’t make their debut until the mid 1800s. Of course the term large is relative here. Today’s state of the art facilities dwarf this one-room aquarium German naturalist Anton Dohrn added to his Zoological Station in Naples Villa Comunale Park in 1874. But don’t let that keep you from visiting. While it is tiny compared to its modern counterparts, this little 19th century aquarium is an architectural, scientific and historical gem. And according to the SZN Institute, it is the only one left of its kind.

Entering the aquarium hall as it was once called, you are met with Dohrn’s original design. Large tanks encircle three of the room’s walls and a double row down the middle splits the room in half. Illuminated only by sunlight streaming in from above the tanks, it feels like dusk, made only darker by the volcanic rock that lines the sides of the tanks.

Ranging in size from 250 to 69,000 liters, the tanks are filled with fresh seawater pumped in from the Bay. And the system they use today is based on the semi-open circulation system developed for Dohrn by English Aquarist William Alford Lloyd. Inside the tanks, the only inhabitants you’ll find are the fauna and marine species indigenous to the Gulf of Naples – octopus and squid, starfish and sea urchins, eels, red coral and sea horses, and sea turtles large and small.