Есть ли лучший способ писать строки HTML на PHP?

I find myself writing a lot of functions in PHP that return HTML code. They may look something like this:

function html_site_head()
{
    return
        "
            <div id=\"site_header\">
                <div id=\"site_header_inner\">
                    <div id=\"site_header_logo\"></div>

                    <div id=\"site_header_countdown\">BARE XX DAGER IGJEN</div>
                </div>
            </div>
        ";
}

Now I can swear I've seen better ways to write long strings in PHP. I like python's way of doing it:

return """
    <div id="site_header">
        <div id="site_header_inner">
            <div id="site_header_logo"></div>

            <div id="site_header_countdown">BARE XX DAGER IGJEN</div>
        </div>
    </div>
"""

As you don't have to escape quotation marks. An alternative is using single quotation marks, but that means no using PHP variables directly in the string. I swear I've seen something like this in PHP:

return <<<
    <div id="site_header">
        <div id="site_header_inner">
            <div id="site_header_logo"></div>

            <div id="site_header_countdown">BARE XX DAGER IGJEN</div>
        </div>
    </div>

Or something similar. Could someone refresh my memory on this?

Thanks