How you can apply

Order Deny,Allow
Deny from all

for directory localhost/content/ with just one .htaccess in localhost/.htaccess, without httpd.conf ? <Directory> isn't permitted inshtaccess

Can't you place the files outdoors the documentroot from the website?

Only solution I discovered only agreed to be redirecting when somebody attempts to achieve that directory.

Redirect permanent /content/ http://localhost

/Emil