From a7f5ce6b7ba62f87996f88ed45f18e37117b7218 Mon Sep 17 00:00:00 2001
From: Jody Klymak <jklymak@gmail.com>
Date: Fri, 25 Apr 2025 16:51:15 -0700
Subject: [PATCH] Backport PR #29965: Document Axes.spines

---
 doc/api/axes_api.rst         | 1 +
 lib/matplotlib/axes/_base.py | 6 ++++++
 2 files changed, 7 insertions(+)

diff --git a/doc/api/axes_api.rst b/doc/api/axes_api.rst
index 06893dd95c57..7e4b707f7dc5 100644
--- a/doc/api/axes_api.rst
+++ b/doc/api/axes_api.rst
@@ -38,6 +38,7 @@ Attributes
 
    Axes.viewLim
    Axes.dataLim
+   Axes.spines
 
 Plotting
 ========
diff --git a/lib/matplotlib/axes/_base.py b/lib/matplotlib/axes/_base.py
index bfee2091a1a6..0078b799b159 100644
--- a/lib/matplotlib/axes/_base.py
+++ b/lib/matplotlib/axes/_base.py
@@ -566,6 +566,12 @@ class _AxesBase(martist.Artist):
     dataLim: mtransforms.Bbox
     """The bounding `.Bbox` enclosing all data displayed in the Axes."""
 
+    spines: mspines.Spines
+    """
+    The `.Spines` container for the Axes' spines, i.e. the lines denoting the
+    data area boundaries.
+    """
+
     xaxis: maxis.XAxis
     """
     The `.XAxis` instance.