Continuous scroll

I’m re-developing my wordpress website and like the idea of allowing my readers to continuously scroll through my posts, like is done all the news sites these days.

My site content lends itself well to this since it’s a series of travel posts/stories. So for example I might have a category called Austria, then within that four or five posts about my trip there.

I’d like to this to run on the single.php or make use of ajax to show/expand the content when someone clicks on the “read more” link in a specific category archive.

The important part is that pagination still exists, and that the URL changes to show the post being viewed.

What’s the best way of going about this? I prefer not to use plugins if possible.

Can anyone point me in the right direction?