function validate() {
	if ( (document.getElementById("realname").value.length < 1) || (document.getElementById("add1").value.length < 1) || (document.getElementById("city").value.length < 1) || (document.getElementById("code").value.length < 1) || ( (document.getElementById("email").value.length < 1) && (document.getElementById("tel").value.length < 1) ) ) {
		alert("Please give us your name, full address, and telephone or email contact details.")
		return false;
	}
	
	if ( (document.getElementById("depyear").value.length != 4) || (document.getElementById("arryear").value.length != 4) ) {
		alert("Please enter a 4 digit year for both arrival and departure dates.")
		return false;
	}
	
	return true;
}