dual graphs
... that dual graphs can explain why the halls and walls of many mazes form interlocking trees?
... that <b id="mwAb8"><a href="./Dual_graph" id="mwAcA" rel="mw:WikiLink" title="Dual graph">dual graphs</a></b> can explain why the halls and walls of many <a href="./Maze" id="mwAcE" rel="mw:WikiLink" title="Maze">mazes</a> <i id="mwAcI">(example pictured)</i> form interlocking <a href="./Tree_(graph_theory)" id="mwAcM" rel="mw:WikiLink" title="Tree (graph theory)">trees</a>?