SkyBlock is a map that tests how well you know Minecraft. Like, really know it. Past the surface stuff down to its deepest quirks and idiosyncrasies. You're placed on an small, three block deep island in the sky. On that island is a tree and a chest. In that chest is a bucket of lava and a block of ice.
Not much, right? So build a Nether Portal. Or craft 10 Snow Golems, cook 10 fish, and any of the other challenges listed on the map's download page. It's all possible, but requires being extra careful that you never waste a block. Download SkyBlock here.
While nothing like the scale of Crafting Azeroth or WeserosCraft, Newcraft City is still a beautifully realized creation. It takes a bunch of famous skyscrapers, including a restored World Trade Centre, and mashes them together into an architect's paradise of a landscape. Best viewed with the custom hi-res texture pack, Newcraft City is a great map to stick in Creative mode to have a wander through. It also contains a tram system to take you around the various sights and a bridge to the new Vector City, where, at the furthest edge, you'll find a Biohazard wall keeping back hordes of mobs. Download Newcraft City here.
You'll see a few creations from talented mapmaker Hypixel in this list. Herobrine's Mansion is a classic, which uses the legend of Minecraft's hard-to-delete spectre as the basis for a sprawling adventure through a haunted mansion. Inside you'll find tough mobs, custom weapons and a series of cleverly tuned bosses. Naturally, this makes it hard as all heck, and while it can be played in single-player, you're better off bringing a friend. Download Herobrine's Mansion here.
Vechs' Super Hostile series is a collection of maps designed to make Minecraft hard. Really, really hard. Some are short on resources, some are full of traps, others are full of monsters. There's a wide variety of worlds on offer, from the giant trees of Canopy Carnage to the sparsely lit Black Desert. But while each map is themed around a different idea, they all have one thing in common: they want you dead. Download the Super Hostile series here.
Epic Jump Map: Butter Edition
The Epic Jump Map series is responsible for some of the best parkour courses available for Minecraft. The Butter Edition is a personal favourite, although not because of its unusual theme. To recap: squids rule the world, the land is corrupted, and everything is yellow for some reason. Forget all that; the real reason to take a look is a well-paced campaign that intersperses its tricky jumping puzzles with periods of combat. Or fleeing, if you prefer. Download Epic Jump Map: Butter Edition here.