Change theme:   
It is possible to generate breadcrumbs out of the structure. Be warned, it is messy:

<a href="{{ site.root_item.url }}">{{ site.root_item.title }}</a></li>
{% for item in site.menuitems %}
{% if item.selected? %}
   &gt; <a href="{{ item.url }}">{{ item.title }}</a>
   {% if item.children? %}
      {% for level2 in item.children %}
      {% if level2.selected? %}
         &gt; <a href="{{ level2.url }}">{{ level2.title }}</a>
         {% if level2.children? %}
            {% for level3 in level2.children %}
            {%if level3.selected? %}
               &gt; <a href="{{ level3.url }}">{{ level3.title }}</a>
               {% if level3.children? %}
                  {% for level4 in level3.children %}
                  {% if level4.selected? %}
                     &gt; <a href="{{ level4.url }}">{{ level4.title }}</a>
                  {% endif %}
                  {% endfor %}
               {% endif %}
            {% endif %}
            {% endfor %}
         {% endif %}
      {% endif %}
      {% endfor %}
   {% endif %}
{% endif %}
{% endfor %}