The Tunel de L’ Atlantida is the longest anchialine lavatube in the world. That means it is the longest underwater lavatube uptill now.
The overall length from this tube is now 1,968km. and its depth is -64m.
The underwater part is starting at the Jameo del Agua, and can due to natural protection under Spanish law only be visited a few times a year for scientific purposes.
There have been quite some investigations in this very special environment and these are still going on. For some publication view the list under the link to Corona system page.
One of the earlier visits into the system was from Grupo de Espeleologia de Tenerife Benisahara-ULL in 2007
Beneath some pictures from that expedition in 2007:
For more information on recent scientific investigations called “proyecto-sublantida” you can visit the link to the page from GAMA-UNED
a recent film about the sytem you can visit on this link from the youtube site.
Underneath you find some pictures from the last expedition in november 2020 from the Proyecto-sublantida