Below are a couple of examples to quick start with the Gmaps module
{exp:entry_archive:entries dynamic="no" sort="desc" channel="your_channel"}
<ul>
{years}
<li>
{year format="%y"}
<ul>
{months}
<li>
{month format="%M"}
<ul>
{entries}
<li>{title}</li>
{/entries}
</ul>
</li>
{/months}
</ul>
</li>
{/years}
</ul>
{/exp:entry_archive:entries}
{exp:entry_archive:entries dynamic="no" sort="desc" channel="your_channel"}
<ul>
{years}
<li>
{year format="%Y"}
<ul>
{entries}
<li>{title}</li>
{/entries}
</ul>
</li>
{/years}
</ul>
{/exp:entry_archive:entries}