<div style = "relative;">

<div id = "layer1" style =  " width:1364px; height:1201px; absolute; left:0px; top:0px; z-index:-1; overflow-x:scroll; overflow-y:scroll;" >
<img class="size-full wp-image-252 alignnone" alt="naver_subway" src="http://dkwkrjtk3.cafe24.com/wp-content/uploads/2013/10/naver_subway.jpg" width:2164px; height:2001px; usemap='#map1' />
<map name="map1" >
   <area shape='rect' coords='345,375,400,397' href="http://www.naver.com" target='_blank' /> <!--홍대입구-->
   <area shape='rect' coords='440,383,465,404' href="http://www.naver.com" target='_blank' /> <!--이대-->
   <area shape='rect' coords='802,383,824,404' href="http://www.naver.com" target='_blank' /> <!--신당-->
   <area shape='rect' coords='871,399,900,416' href="http://www.naver.com" target='_blank' /> <!--왕십리-->
   <area shape='rect' coords='833,375,865,398' href="http://www.naver.com" target='_blank' /> <!--상왕십리-->
   <area shape='rect' coords='936,493,989,509' href="http://www.naver.com" target='_blank' /> <!--건대입구-->
   <area shape='rect' coords='847,685,877,709' href="http://www.naver.com" target='_blank' /> <!--선릉-->
   <area shape='rect' coords='800,684,820,708' href="http://www.naver.com" target='_blank' /> <!--강남-->
   <area shape='rect' coords='679,693,696,717' href="http://www.naver.com" target='_blank' /> <!--방배-->
   <area shape='rect' coords='513,692,530,718' href="http://www.naver.com" target='_blank' /> <!--봉천-->
   <area shape='rect' coords='462,694,481,716' href="http://www.naver.com" target='_blank' /> <!--신림-->
   <area shape='rect' coords='252,602,286,623' href="http://www.naver.com" target='_blank' /> <!--도림천-->
   <area shape='rect' coords='883,693,899,717' href="http://www.naver.com" target='_blank' /> <!--삼성-->
   <area shape='rect' coords='947,626,986,656' href="http://www.naver.com" target='_blank' /> <!--잠실-->
   <area shape='rect' coords='971,569,1015,584' href="http://www.naver.com" target='_blank' /> <!--잠실나루-->
   <area shape='rect' coords='294,426,333,444' href="http://www.naver.com" target='_blank' /> <!--합정-->


</map>
 </div>

이코드에서 이미지를 div태그에 넣고 div 태그 크기에맞게 스크롤링 할수있게 하고싶은데,
이미지크기를 img태그에서 width:2164px; height:2001px;라고 지정했는데도 이미지크기가
img가아니라 div태그 에서 지정한 width:1364px; height:1201px; 따라 줄어드는데 뭐가문제인가요?