title: Why is my http://schema.org/BreadcrumbList not validating?
body: <p>I'm using schema.org microdata on my web site but I'm struggling with the <a href="https://schema.org/BreadcrumbList" rel="nofollow">BreadcrumbList</a> as Google's <a href="https://developers.google.com/structured-data/testing-tool?url=http%253A%252F%252Fwww.rossmod.co.uk%252Frc-cars%252Fcar-kits%252Ftamiya-lunch-box-58347.html" rel="nofollow">structured data testing tool</a> will not validate it.  It looks correct and I can't see what's wrong.</p>
  
  <p>You can click the above link to see the errors, but to summarise, Google says that the itemtype attribute has an invalid value for each of the items and also complains that the mainEntityOfPage attribute is missing from the list.  I did try adding mainEntityOfPage in a meta tag but it still complained about it.</p>
  
  <p>What am I doing wrong?</p>
  
  <pre><code>&lt;ul itemscope="" itemtype="http://schema.org/BreadcrumbList"&gt;
      &lt;li class="home" itemscope="" itemprop="itemListElement" itemtype="http://schema.org/ListItem"&gt;
          &lt;a href="http://www.rossmod.co.uk/" title="Go to Home Page" itemprop="item"&gt;&lt;span itemprop="name"&gt;Home&lt;/span&gt;&lt;/a&gt;
          &lt;span&gt;/ &lt;/span&gt;
          &lt;meta itemprop="position" content="1"&gt;
      &lt;/li&gt;
      &lt;li class="category3" itemscope="" itemprop="itemListElement" itemtype="http://schema.org/ListItem"&gt;
          &lt;a href="http://www.rossmod.co.uk/rc-cars.html" title="" itemprop="item"&gt;&lt;span itemprop="name"&gt;RC Cars&lt;/span&gt;&lt;/a&gt;
          &lt;span&gt;/ &lt;/span&gt;
          &lt;meta itemprop="position" content="2"&gt;
      &lt;/li&gt;
      &lt;li class="category10" itemscope="" itemprop="itemListElement" itemtype="http://schema.org/ListItem"&gt;
          &lt;a href="http://www.rossmod.co.uk/rc-cars/car-kits.html" title="" itemprop="item"&gt;&lt;span itemprop="name"&gt;Car Kits&lt;/span&gt;&lt;/a&gt;
          &lt;span&gt;/ &lt;/span&gt;
          &lt;meta itemprop="position" content="3"&gt;
      &lt;/li&gt;
      &lt;li class="product"&gt;
          &lt;strong&gt;Tamiya Lunch Box. No ESC [58347]&lt;/strong&gt;
      &lt;/li&gt;
  &lt;/ul&gt;
  </code></pre>