How do I position an image at the bottom of div?

I want an html image to be flush with the bottom of a div tag. I can't seem to find a way to accomplish this.

Here is my HTML:

<div class="span8">
  <img src="/img/play-shot1.jpg" class="text-center shadow">
</div>

The problem is that the div is nested within other divs that have padding or margins.

Add relative positioning to the wrapping div tag, then absolutely position the image within it like this:

CSS:

.div-wrapper {
    position: relative;
    height: 300px;
    width: 300px;
}

.div-wrapper img {
    position: absolute;
    left: 0;
    bottom: 0;
}

HTML:

<div class="div-wrapper">
    <img src="blah.png"/>
</div>

Now the image sits at the bottom of the div.

Using flexbox:

HTML:

<div class="wrapper">
    <img src="pikachu.gif"/>
</div>

CSS:

.wrapper {
    height: 300px;
    width: 300px;
    display: flex;
    align-items: flex-end;
}

As requested in some comments on another answer, the image can also be horizontally centred with justify-content: center;

< img style="vertical-align: bottom" src="blah.png" >

Works for me. Inside a parallax div as well.