Since you are printing several lines of HTML, I would suggest using a heredoc as such:
echo <<<HTML
<div>
<a class="fragment" href="$url">
<div>
HTML;
HTML can be anything as long as you use the same tag both in the beginning and the end. The end tag must however be on its own line without any spaces or tabs. With that said, specifically HTML also has the benefit that some editors (e.g. VIM) recognise it and apply HTML syntax colouring on the text instead of merely coluring it like a regular string.
If you want to use arrays or similar you can escape the variable with {} as such:
echo <<<HTML
<div>{$someArray[1]}</div>
HTML;