$kirby->root('collections')
The directory where all your shared collections are stored.
Example
<?= $kirby->root('collections') ?>
Custom setup
If you want to overwrite the root you can do this in your index.php
by passing a custom roots setup to the Kirby constructor.
<?php
include 'kirby/bootstrap.php';
$kirby = new Kirby([
'roots' => [
'collections' => '/absolute/path/to/custom/root',
],
]);
echo $kirby->render();