Below is a script that I use to create a UK map (England is split across 3 images) that highlights the country that you have moused over ( the page the script is taken from:
Nav list)
This script goes into the head for the page and preloads all the images
<script language="Javascript">
EngnormalImg= new Image();
EngnormalImg.src= 'images/UK_Map/englebw.jpg';
EngnormalImg2=new Image();
EngnormalImg2.src= 'images/UK_Map/englnbw.jpg';
EngnormalImg3=new Image();
EngnormalImg3.src= 'images/UK_Map/englsbw.jpg';
WalnormalImg= new Image();
WalnormalImg.src= 'images/UK_Map/walbw.jpg';
SconormalImg= new Image();
SconormalImg.src= 'images/UK_Map/scotbw.jpg';
EnghiddenImg= new Image();
EnghiddenImg.src= 'images/UK_Map/engle.jpg';
EnghiddenImg2=new Image();
EnghiddenImg2.src= 'images/UK_Map/englnc.jpg';
EnghiddenImg3=new Image();
EnghiddenImg3.src= 'images/UK_Map/engls.jpg';
WalhiddenImg= new Image();
WalhiddenImg.src= 'images/UK_Map/wal.jpg';
ScohiddenImg= new Image();
ScohiddenImg.src= 'images/UK_Map/scotc.jpg';
function EnglandOver()
{
WalesOut();
ScotlandOut();
document.UK_Map3.src=EnghiddenImg.src;
document.UK_Map4.src=EnghiddenImg2.src;
document.UK_Map5.src=EnghiddenImg3.src;
}
function EnglandOut()
{
document.UK_Map3.src=EngnormalImg.src;
document.UK_Map4.src=EngnormalImg2.src;
document.UK_Map5.src=EngnormalImg3.src;
}
function EnglandLink()
{
url = '/England/index.php'
parent.location.href= url
}
function WalesOver()
{
ScotlandOut();
EnglandOut();
document.UK_Map2.src=WalhiddenImg.src;
}
function WalesOut()
{
document.UK_Map2.src=WalnormalImg.src;
}
function WalesLink()
{
url = '/Wales/index.php'
parent.location.href= url
}
function ScotlandOver()
{
EnglandOut();
WalesOut();
document.UK_Map1.src=ScohiddenImg.src;
}
function ScotlandOut()
{
document.UK_Map1.src=SconormalImg.src;
}
function ScotlandLink()
{
url = '/Scotland/index.php'
parent.location.href= url
}
</script>
In the body of your page
<a id='Scotland' name='Scotland' onclick='ScotlandOver()' ondblclick='ScotlandLink()'><!--onMouseOut=ScotlandOut()-->
<img src='images/UK_Map/scotbw.jpg' name='UK_Map1' alt='Scotland - Link to mountains, routes, climbs, etc' border='0' width='173' height='111' /></a>
<a id='Wales' name='Wales' onclick='WalesOver()' ondblclick='WalesLink()'><!--onMouseOut=WalesOut()-->
<img src='images/UK_Map/walbw.jpg' name='UK_Map2' alt='Wales - Link to mountains, routes, climbs, etc' border='0' width='118' height='47' />
</a>
<a id='England' name='England' onclick='EnglandOver()' ondblclick='EnglandLink()'><!--onMouseOut='EnglandOut()'-->
<img src='images/UK_Map/englebw.jpg' name='UK_Map3' alt='England - Link to mountains, routes, climbs, etc' border='0' width='58' height='118' />
</a>
<a id='England1' name='England1' onclick='EnglandOver()' ondblclick='EnglandLink()'><!--onMouseOut='EnglandOut()'-->
<img src='images/UK_Map/englnbw.jpg' name='UK_Map4' border='0' alt='England - Links to mountains, routes, climbs, etc' width='120' height='27' />
</a>
<a id='England2' name='England2' onclick='EnglandOver()' ondblclick='EnglandLink()'><!--onMouseOut='EnglandOut()'-->
<img src='images/UK_Map/englsbw.jpg' name='UK_Map5' border='0' alt='England - Links to mountains, routes, climbs, etc' width='118' height='35' />
</a>
Hope this helps...