this is the right answer:
<h1><a href="www.example.com">Example!</a></h1>
In HTML 4.01 and XHTML 1.1 and older:
h1
may contain an a
a
may not contain an h1
So <h1><a>…</a></h1>
In the HTML 5 draft:
h1
may contain an a
a
may contain an h1
(but only if the a
is somewhere an h1
is allowed — see the comments on this answer)So either, but browser support may vary (such is life on the bleeding edge).
HTML4, XHTML
<h1><a href="">Text</a></h1>
HTML5
<h1><a href="">Text</a></h1>
<a href=""><h1>Text</h1></a>
It's acceptable in HTML5 as the anchor tag's been made 'block level'.
Some good info on block level and inline level tags can be found at http://www.webdesignfromscratch.com/html-css/css-block-and-inline/