El Ojo

El Ojo (lit. 'The Eye') is an uninhabited circular rotating floating island located within a slightly larger circular lake in the Paraná Delta in the Buenos Aires Province, Argentina.

Description
The island is unique among its floating counterparts as its shape is almost perfectly circular. As the island is constantly rotating on its own axis due to the flow of the river beneath it, shearing occurs around its outer edge, eroding the island into its circular shape, similar to ice disks. The island is approximately 118 m in diameter, though will get smaller over time as the erosion occurs. It is not yet known how or when the island was initially formed, with the first known Google Earth imagery being dated 2003. The island was named because of its resemblance to an eye when viewed from above: as the island rotates within its surrounding circular lake, the eye appears to move. The island has been compared to a similarly shaped and rotating floating ice disk phenomenon observed in the Presumpscot River near Westbrook, Maine.

El Ojo was discovered by Argentinian filmmaker Sergio Neuspiller and research has shown that the island has existed at least since 2003. In 2016, Neuspiller and hydraulic engineer Ricardo Petroni started crowdfunding an expedition to the island hoping to perform scuba diving, drone data collection, and soil and plant analysis; however, their fundraising attempts failed, reaching only US$9898 of their US$50000 goal. On 10 October 2016, Kickstarter eventually declared the fundraising campaign unsuccessful.