D&D Notable Location - Underwater

A location that is known locally or further afield, as a landmark, place of history, magical danger or otherwise noteworthy.
Encounters underwater bring visions of murky seas, vast reefs and dark depths. They might occur in a kelp bed, an underwater cave or by a long-forgotten shipwreck

tools for - dnd5e location quest underwater

terrain:

An eerie glade. It is at the top of a hill. It is where a fiend was imprisoned. was the site of a great tragedy.
Eon Watcher. On a cliff-face is a timer of glass as tough as steel. It slowly fills with shells before resetting. Blessed by a sea deity.
Ruins of Foamdock is a ruins.
The LonelyGlen is a foreboding cliff. It is at the top of a hill. It has a great ritual that occurs year. It is watched by a water elementalt.
A cave entrance lined with draconic runes. A dormant mechanism is located here along with many large bones.
A floating seaweed garden. It is at a crossroads. It is the birthplace of a scheming oracle.
A lonely lair. It is in a field.
The Fane of the Resplendent Singer is a decorated temple to a power of chaos. It is protected by a swarm of crustaceans.
Ruins of Fisher's Rock is a ruins. It is at a crossroads. It is often home to spiders. It is protected by a spirit.
A colorful canyon. It is associated with a power of peace.