Just like normal rails in Minecraft, detector rails can be placed on any solid block below or above water and some other blocks like hoppers, upside-down slabs, and upside-down stairs. Players should note that it can only be placed underwater in version 1.17 and released after it.
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To place them, players need to press the use button (right-click by default on computers) while aiming at them. They cannot be placed on the side or bottom of a block. If the player tries to, they will be placed on the block next to it. Detector rails can be connected to any other type of rail to form a track for minecarts.
Edited by Srijan Sen

