diff --git a/tests/Unit/Domain/Geometry/MultiGeometryTest.php b/tests/Unit/Domain/Geometry/MultiGeometryTest.php
index 439d0fa..51cc630 100644
--- a/tests/Unit/Domain/Geometry/MultiGeometryTest.php
+++ b/tests/Unit/Domain/Geometry/MultiGeometryTest.php
@@ -16,7 +16,7 @@ final class MultiGeometryTest extends TestCase
 
     private Point $point;
     private Polygon $polygon;
-    private $geometries;
+    private array $geometries;
 
     protected function setUp(): void
     {