Multisite – New Site Default Set-up

Is there a way to create a “template” site and then create a back-up (or something) so that it can be restored and used when creating new sites with all of the plugins installed, categories created etc?

Each of my sites are going to look the same with the same plugins installed, pages (at start-up), default users, categories etc. I am just looking at ways to reduce the time require to set-up a new site