Great Minecraft Maps by an Excellent development team, all free to download.
They truly put their effort into their work, it is a pleasure to have it all for free.
They also have an amazing YouTube channel about games and other stuff since 2014.
Tip for consumers: If you have had any issues and/or need a refund, they will allow it anytime (before 14 days after purchase are up) as long as it is appropriate with your proof of purchase (email).
At the footer of the website is all the links available on the site, so scroll down there if you get lost.
Also, all their Minecraft Maps can be downloaded through “Minecraft Maps” tab.
This website also has a community forum, so that you can find tips and tricks for issues or any community based improvements.