Mis-typed wordpress address in settings: WP addr. URL

I was editing General Settings and intended to change site address BUT instead changed WordPress address URL. WP is installed at http://kisshorses.com/main BUT now the general setting for the URL is http://kisshorses.com/start.

When I go to http://kisshorses.com/main I get a kind of site map.
When I try to go to something like http://kisshorses.com/main/?page_id=6 it automatically changes to http://kisshorses.com/front/?page_id=6 and I get a 404 error.

How can I get the WordPress URL reset to http://kisshorses.com/main ??