function init_map() {
    var latlng = new google.maps.LatLng(39.902780, 116.256613);
    var myOptions = {
        zoom: 16,
        center: latlng,
        mapTypeId: google.maps.MapTypeId.ROADMAP
    };
    var mapDiv = document.getElementById('map');
    var map = new google.maps.Map(mapDiv, myOptions);

    function attachMessage(marker, text) {
        var infowindow = new google.maps.InfoWindow({ 
            content: text
        });
        google.maps.event.addListener(marker, 'click',
            function() {
                infowindow.open(map, marker);
            });
        return infowindow;
    }
    
    var location = new google.maps.LatLng(39.901389, 116.255556);
    var marker = new google.maps.Marker({
        position: location,
        map: map,
        title: '十一学校'
    });
    var infowindow = attachMessage(marker, '<h2>北京十一学校</h2><p>北京市十一学校（英文：Beijing National Day School）是20世纪50年代建立的集小学、初中、高中于一体的北京市学校，位于北京市海淀区。</p><a href="place.php?id=1">详细信息</a>');
    var location = new google.maps.LatLng(39.900389, 116.255556);
    var marker = new google.maps.Marker({
        position: location,
        map: map,
        title: '国际部'
    });
    var infowindow = attachMessage(marker, '<h2>国际部大楼(综合楼)</h2><p>国际部大楼，也叫综合楼。功能繁多，各色人等皆有。</p><a href="place.php?id=2">详细信息</a>');
    var location = new google.maps.LatLng(39.9036616818426, 116.259280456865);
    var marker = new google.maps.Marker({
        position: location,
        map: map,
        title: '新疆餐厅'
    });
    var infowindow = attachMessage(marker, '<h2>西北穆斯林餐厅</h2><p>新疆人开的一家餐厅，现在已经关了，换成了另一家。</p><a href="place.php?id=3">详细信息</a>');
    var location = new google.maps.LatLng(39.9036616818426, 116.257153465117);
    var marker = new google.maps.Marker({
        position: location,
        map: map,
        title: '红房子'
    });
    var infowindow = attachMessage(marker, '<h2>厚德红房子</h2><p>红房子是一家餐厅，在北门外，物美价廉。</p><a href="place.php?id=4">详细信息</a>');
    var location = new google.maps.LatLng(39.9036616818426, 116.256810142363);
    var marker = new google.maps.Marker({
        position: location,
        map: map,
        title: '潇湘味道'
    });
    var infowindow = attachMessage(marker, '<h2>潇湘味道</h2><p>潇湘味道是北门外众多餐馆中的一家</p><a href="place.php?id=5">详细信息</a>');
    var location = new google.maps.LatLng(39.9022799980211, 116.254817261065);
    var marker = new google.maps.Marker({
        position: location,
        map: map,
        title: '大操场'
    });
    var infowindow = attachMessage(marker, '<h2>十一学校大操场</h2><p>大操场是十一学子主要的户外活动场所</p><a href="place.php?id=6">详细信息</a>');}