Image change scroll page to top

[regoch]

Hi, I have this simple code for gallery on my page.  And everything working fine but when i click on small picture to change big picture if I'm page scroll up to top of page. So i scroll to the gallery change picture ad page scroll up to the top. What could be the reason?  Here is live axample:

http://www.galerija-galiotovic.kus-sinj.hr/hr/fotogalerija/3/test-hrvatski#

  <table id="Table_galerija">

  <tr>
    <td style="width:520px;height:445px;vertical-align:top;padding:20px;">
      <h2 style="position:absolute;top:200px;color:#FFF;" id="naslov">Test hrvatski</h2>
     	  <div id="slika_velika"><img id="glavna_slika" style="max-height:390px;max-width:520px;vertical-align:middle;" src="/slike/10012012_7119092522.jpg" alt="KUS Sinj" /></div></td>
    <td>

        <div class="slikica"><a href="#" onclick="document.getElementById('glavna_slika').src='/slike/10012012_7119092522.jpg'"><img src="/slike/thumbnails/10012012_7119092522.jpg" style="max-height:88px;max-width:125px;vertical-align:middle;" alt="KUS Sinj" /></a></div>
    <div style="height:14px;"></div>
        <div class="slikica"><a href="#" onclick="document.getElementById('glavna_slika').src='/slike/12012012_7509043961.jpg'"><img src="/slike/thumbnails/12012012_7509043961.jpg" style="max-height:88px;max-width:125px;vertical-align:middle;" alt="KUS Sinj" /></a></div>
    <div style="height:14px;"></div>
        <div class="slikica"><a href="#" onclick="document.getElementById('glavna_slika').src='/slike/12012012_9295689431.jpg'"><img src="/slike/thumbnails/12012012_9295689431.jpg" style="max-height:88px;max-width:125px;vertical-align:middle;" alt="KUS Sinj" /></a></div>
    <div style="height:14px;"></div>
        <div class="slikica"><a href="#" onclick="document.getElementById('glavna_slika').src='/slike/12012012_8527430603.jpg'"><img src="/slike/thumbnails/12012012_8527430603.jpg" style="max-height:88px;max-width:125px;vertical-align:middle;" alt="KUS Sinj" /></a></div>
    <div style="height:14px;"></div>
        <div class="slikica"><a href="#" onclick="document.getElementById('glavna_slika').src='/slike/12012012_2126924535.jpg'"><img src="/slike/thumbnails/12012012_2126924535.jpg" style="max-height:88px;max-width:125px;vertical-align:middle;" alt="KUS Sinj" /></a></div>

    <div style="height:14px;"></div>
<div id="gori"><a href="#" onmousedown="moveup()" onmouseup="clearTimeout(moveupvar)"><img src="/images/gori.png" width="119" height="23" alt="Top Sport" /></a></div>
    <div id="doli"><a href="#" onmousedown="movedown()" onmouseup="clearTimeout(movedownvar)"><img src="/images/doli.png" width="119" height="23" alt="Top Sport" /></a></div></td>
  </tr>
  </table>