This page explains how to find the Lanno Kooh shrine.
How to Reach the Shrine
This shrine is west of Hebra Tower. Just go west from the tower until the Sheikah Sensor leads you to the shrine. However, you will find that this shrine is surrounded by freezing water, which will quickly deplete your health if you try to swim in it, even if you are using armor or elixirs to protect from the cold.
To reach the shrine, first go northwest from the shrine and look for a tree near the river. Chop down the tree such that it falls into the river, then follow it. After the log falls down the waterfall, float down onto the log. When you have safely landed on the log, crouch on it. Then when the log stops at the shrine, you can walk off of it onto the shrine's island.
About the Shrine
The treasure chest in the shrine contains a Gold Rupee.