function ocultartodo(){
	document.getElementById('barcelona').style.visibility='hidden';
	document.getElementById('madrid').style.visibility='hidden';
	document.getElementById('bilbao').style.visibility='hidden';
	document.getElementById('valencia').style.visibility='hidden';
	document.getElementById('zaragoza').style.visibility='hidden';
	document.getElementById('valladolid').style.visibility='hidden';
	document.getElementById('mallorca').style.visibility='hidden';
}