Pretty cool what I came across in Tafsir ibn Kathir and Sahih Bukhari:

In Tafsir Ibn Kathir, Surah Kahf, Chapter 'The Story of Musa and Al Khidr' he mentions:
﴿فَلَمَّا بَلَغَا مَجْمَعَ بَيْنِهِمَا نَسِيَا حُوتَهُمَا﴾

(But when they reached the junction of the two seas, they forgot their fish,) He had been commanded to carry a salted fish with him, and it had been said to him, when you lose the fish, that will be a sign that you have reached the right place. So they set out and traveled until they reached the junction of the two seas, where there was a spring called `Ayn Al-Hayat (the Spring of Life). They went to sleep there, and the fish felt the drops of that water, so it came back to life. It was in a vessel with Yusha`, upon him be peace, and it jumped out of the vessel towards the sea. Yusha` woke up and the fish fell into the water and started to swim through the water, leaving a track or channel behind it.
I did a bit of research and came across mention of the Spring in a hadith in Bukhari. The hadith is long, so the relevant excerpt follows:
Bukhari :: Book 6 :: Volume 60 :: Hadith 251

Narrated Said bin Jubair:

[...]
Moses said, 'O my Lord ! How can meet him?' Allah said, 'Take a fish in a basket and wherever the fish is lost, follow it (you will find him at that place). So Moses set out along with his attendant Yusha' bin Nun, and they carried with them a fish till they reached a rock and rested there. Moses put his head down and slept. (Sufyan, a sub-narrator said that somebody other than 'Amr said) 'At the rock there was a water spring called 'Al-Hayat' and none came in touch with its water but became alive. So some of the water of that spring fell over that fish, so it moved and slipped out of the basket and entered the sea. When Moses woke up, he asked his attendant, 'Bring our early meal' (18.62).

[...]
Does anyone have any more info on it from hadiths etc? It's like the fountain of life, any idea where it can be?