[php]Where comes this "1" from?

Hey all,

I am making a site, and a made a php code, but when i test it there will appear a 1 at the bottom of the page that i didn’t put there. I’ve checked the code but can’t find it…

Here is the code of the index:

<?php include('header.php'); ?>

$pagina = "" .strtolower($_GET['page']).".php";
if (file_exists($pagina))
echo include($pagina);
echo include('home.php');
<?php include('footer.php'); ?>

And if you want to look at the site its over here:

So thanks for helping.