diff --git a/geom/aabb.hpp b/geom/aabb.hpp
index f4d23728..b37ca6ab 100644
--- a/geom/aabb.hpp
+++ b/geom/aabb.hpp
@@ -48,7 +48,6 @@ namespace cruft::geom {
         }
 
 
-
         ///////////////////////////////////////////////////////////////////////
         extent<S,T>
         magnitude (void) const
@@ -65,6 +64,17 @@ namespace cruft::geom {
         }
 
 
+        //---------------------------------------------------------------------
+        point<S,T>
+        centre (void) const
+        {
+            point<S,T> res;
+            for (std::size_t i = 0; i < S; ++i)
+                res[i] = (lo[i] + hi[i] / 2);
+            return res;
+        }
+
+
         ///--------------------------------------------------------------------
         /// tests whether a point lies within the region, inclusive of borders
         constexpr bool