Cross-Fade between images with CSS in loop

Question

I want to fade between images in a loop (like result here-jsfiddle.net/5M2PD) but purely through CSS, no JavaScript. I tried using key-frames but I

Answer 1

I have taken your fiddle as a base, and made it work without script.

updated demo

I needed to set an id to the HTML

.fadein img {
    position:absolute;
    top:0;
    -webkit-animation-name: fade;
    -webkit-animation-iteration-count: infinite;
    -webkit-animation-duration: 6s;
    animation-name: fade;
    animation-iteration-count: infinite;
    animation-duration: 6s;
}

@-webkit-keyframes fade {
    0% {opacity: 0;}
    20% {opacity: 1;}
    33% {opacity: 1;}
    53% {opacity: 0;}
    100% {opacity: 0;}
}
@keyframes fade {
    0% {opacity: 0;}
    20% {opacity: 1;}
    33% {opacity: 1;}
    53% {opacity: 0;}
    100% {opacity: 0;}
}

#f1 {
    background-color: lightblue;
}
#f2 {
    -webkit-animation-delay: -4s;
    background-color: yellow;
}
#f3 {
    -webkit-animation-delay: -2s;
    background-color: lightgreen;
}

I am setting the keyframes to give aprox 1/3 of the time visible, with apropiate transitions. Then I set different delays for every image, so that they alternate. If you want full browser support, you will need more vendor prefixes. I have used -webkit- and bare property so that you get the idea.