Fill entire div with image & make whole div clickable as a link

I have a circular div which I'd like to fill with an image & make the entire image/div clickable(href) with the mouse pointer changed to a hand type cursor

I've looked up a few examples & tried the below which doesn't load the image into the div. I'd also like to zoom out the image on hover.

How could I achieve this pelase?

<div class="circleDiv">
    <a href='#'></a>
</div>

.circleDiv{
  position: relative;
  background-color: #09f;
  margin: 30px 70px 30px 70px;
  width: 250px;
  height: 250px;
  border-radius: 50%;
}

.circleDiv a{
  background: url("path_to_image") no-repeat right center;
}