What is located on top of the stone wall?
The post is on top of the wall.
    src        edge_attr  dst
0     1  to the right of    3
1     1  to the right of    7
2     1  to the right of   19
3     2   to the left of   17
4     3        on top of   17
..  ...              ...  ...
62   19   to the left of   12
63   19   to the left of    4
64   19   to the left of    7
65   19   to the left of    3
66   19   to the left of    1

[67 rows x 3 columns]