My boss was messing around with this page and suddenly it stopped working and started giving us a 502 Bad Gateway error. Is there anything you can see that explains why this happened?
<ul id="menu">
<li><a href="?p=tenuta_a_deo.html">About A Deo</a></li>
<li>
<a href="?p=our_wines">Our Wines</a>
<ul>
<li><a href="?p=our_wines/tenuta_a_deo_red.html">Tenuta A Deo - Red</a></li>
<li><a href="?p=our_wines/tenuta_a_deo_white.html">Tenuta A Deo - White</a></li>
<li><a href="?p=our_wines/tenuta_a_deo_oil.html">Tenuta A Deo - Oil</a></li>
<li><a href="?p=our_wines/popova_kula.html">Popova Kula</a></li>
<li><a href="?p=our_wines/kokino.html">Kokino</a></li>
</ul>
</li>
<li><a href="?p=lucca_olive_oil.html">Lucca Olive Oil</a></li>
<li>
<a href="?p=vacation_rentals">The Farm</a>
<ul>
<li><a href="?p=vacation_rentals/villa_lucca.html">Villa Lucca</a></li>
<li><a href="?p=vacation_rentals/casa_casciani.html">Casa Casciani</a></li>
<li><a href="?p=vacation_rentals/tenuta_a_deo.html">Tenuta A Deo</a></li>
<li><a href="?p=vacation_rentals/tourist_information.html">Tourist information</a></li>
</ul>
</li>
<li><a href="?p=how_to_purchase.html">How to Purchase</a></li>
<li><a href="?p=gallery.php">Gallery</a></li></ul>
A 502 Bad Gateway error is not caused by static HTML like you just displayed.
The server was probably having an internal error or an error communicating with other servers - maybe there was a (temporary) overload, or another server/service was not reachable. Does it still happen when you clear your cache or use another browser/computer?
Can you tell us more about your webserver, and its links to other servers/services?