Edit in JSFiddle

  /*
     CSS-Tricks Example
     by Chris Coyier
     http://css-tricks.com
  */
  $(function() {
    var koukyo = new google.maps.LatLng(35.685175, 139.7528),
      pointToMoveTo,
      first = true,
      curMarker = new google.maps.Marker({}),
      $el;
    var myOptions = {
      zoom: 15,
      center: koukyo,
      mapTypeId: google.maps.MapTypeId.ROADMAP
    };
    var map = new google.maps.Map($("#map_canvas")[0], myOptions);
    $("#locations li").mouseenter(function() {
      $el = $(this);
      if (!$el.hasClass("hover")) {
        $("#locations li").removeClass("hover");
        $el.addClass("hover");
        if (!first) {
          curMarker.setMap();
        }
        // カスタムデータ属性に合わせて移動
        pointToMoveTo = new google.maps.LatLng($el.attr("data-geo-lat"), $el.attr("data-geo-long"));
        map.panTo(pointToMoveTo);
        // マーカーアイコン設定
        curMarker = new google.maps.Marker({
          position: pointToMoveTo,
          map: map,
          icon: "http://placehold.jp/24/cc9999/ffffff/90x70.png?text=ここ！"
        });      
        first = false;
      }
    });
    $("#locations li:first").trigger("mouseenter");
  });

  /*
   CSS-Tricks Example
   by Chris Coyier
   http://css-tricks.com
*/
  
  * {
    margin: 0;
    padding: 0;
  }
  
  body {
    font: 14px Georgia, serif;
    color: #222;
  }
  
  article,
  aside,
  figure,
  footer,
  header,
  hgroup,
  menu,
  nav,
  section {
    display: block;
  }
  
  #page-wrap {
    width: 100%;
    margin: 20px auto;
  }
  
  #map_canvas {
    width: 100%;
    height: 400px;
    width: 400px;
    float: left;
    position: relative;
    z-index: 30 !important;
  }
  
  #locations {
    list-style: none;
    width: 200px;
    float: left;
  }
  
  #locations li {
    padding: 10px;
    float: left;
    position: relative;
    z-index: 20;
  }
  
  #locations li:hover,
  #locations li.hover {
    background: #ffe8b2
  }
  
  #locations li:hover h3,
  #locations li.hover h3 {
    color: red;
    float: left;
  }
  
  #locations li h3 {
    width: 150px;
  }
  
  #locations li p {
    clear: both;
  }

<div id="page-wrap">
  <ul id="locations">
    <li data-geo-lat="35.685175" data-geo-long="139.7528">
      <h3>皇居</h3>
    </li>

    <li data-geo-lat="35.789966" data-geo-long="139.821961">
      <h3>スカイツリー</h3>
    </li>

    <li data-geo-lat="35.675888" data-geo-long="139.744858">
      <h3>国会議事堂</h3>
    </li>

    <li data-geo-lat="-16.500413" data-geo-long="-151.74149">
      <h3>ボラボラ島</h3>
    </li>

  </ul>

  <div id="map_canvas"></div>

  <div id="more-info">
    <div>


    </div>
  </div>

</div>