Built as a custom creation for a client—which means no, you can’t download it for free—the city itself is 800×800, while if you include the surrounding countryside the size of the map blows out to 1500×1500.
Varuna is a team of Minecraft builders who are so good at it that they get paid for their work.
And their latest work is this enormous recreation of the city of Orario, from the novel/anime series DanMachi.
All of it hand-crafted and looking like a voxel-based city-builder that I would be very excited for.