You can just use a URL like this:
http://en.wikipedia.org/?curid=18630637
This is the shortest form, others are also possible:
http://en.wikipedia.org/wiki?curid=18630637
http://en.wikipedia.org/wiki/Translation?curid=18630637
http://en.wikipedia.org/w/index.php?curid=18630637
Note that MediaWiki ignores the page title if you specify a curid, so even
http://en.wikipedia.org/wiki/FooBar?curid=18630637
leads to the same page.