a ještě jeden hezký způsob
<!DOCTYPE html>
<html>
<body>
<style>
.nav {
height: auto;
float: left;
text-align: center;
list-style: none;
position: relative; top:0px
padding: 0;
margin: 0;
background-color: lightblue;
}
</style>
<table style="width:100%; position:relative;">
<tr>
<th>Col1</th>
<th>Col2</th>
</tr>
<tr>
<td style="vertical-align: top;">
<div class="nav";>
HELLO
</div>
</br>
<div class="nav";>
HELLO
</div>
</td>
<td>
<div style="background-color: lightblue; height:50px; text-align: center;">
HELLO
</div>
<div style="background-color: lightblue;">
HELLO
</div>
<div style="background-color: lightblue;">
HELLO
</div>
<div style="background-color: lightblue;">
HELLO
</div>
</td>
</tr>
</table>
</body>
</html>