diff --git a/app/models.py b/app/models.py
index 6ee089a..5994610 100644
--- a/app/models.py
+++ b/app/models.py
@@ -51,6 +51,7 @@ class Post(db.Model):
     gpx_files = db.relationship('GPXFile', backref='post', lazy='dynamic', cascade='all, delete-orphan')
     comments = db.relationship('Comment', backref='post', lazy='dynamic', cascade='all, delete-orphan')
     likes = db.relationship('Like', backref='post', lazy='dynamic', cascade='all, delete-orphan')
+    map_route = db.relationship('MapRoute', backref='post', uselist=False, cascade='all, delete-orphan', passive_deletes=True)
     
     def get_difficulty_label(self):
         labels = ['Very Easy', 'Easy', 'Moderate', 'Hard', 'Very Hard']
@@ -213,7 +214,7 @@ class MapRoute(db.Model):
     gpx_file_id = db.Column(db.Integer, db.ForeignKey('gpx_files.id'), nullable=False)
     
     # Relationships
-    post = db.relationship('Post', backref=db.backref('map_route', uselist=False))
+    # Relationship now defined on Post with cascade and passive_deletes
     gpx_file = db.relationship('GPXFile', backref='map_route')
     
     def get_coordinates_json(self):