The five hardest Lego sets to build (2025)

What are the hardest Lego sets to build? As you become more and more skilled as a Lego builder, you’ll find that you’re finishing builds faster and faster. Sure, it’s still fun, but where’s the challenge? Well, fret not– we’ve scoured the brick world to find the most complicated Lego sets, sure to give you a true building challenge.

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With that said, Wargamer’s otherLegoguides aren’t short of challenging kits. For some other high level recommendations, read our guides to thebest Lego sets for adultsand the most expensive Lego setsavailable. For now, though…

The hardest Lego sets to build are:

1. Lego Art World Map – most pieces
2. Lego Icons Eiffel Tower – tallest Lego set
3. Lego Technic Liebherr Crawler Crane LR 13000 – ultimate engineering challenge
4. Lego Super Mario 64 Question Mark Block – most delicate Lego set
5. Lego Creator Expert Taj Mahal – eye-watering

1. Lego Art World Map

The most pieces in any Lego set

Pros

• Makes beautiful decor for your house
• Make it your own – record your international visits
• Can be assembled in three ways to reflect your region’s world map

Cons

• Needs masses of space to sort bricks
• You’ll need a big wall to display it
• An endurance challengemore than a skill challenge

With 11,695 pieces, the Lego Art World Map currently has more pieces than any other commercial Lego set. Like much of the Lego Art series, this is a strictly 2D kit, consisting of black canvas backplates on which you’ll stick thousands of white and coloured dots, filling in the continents and oceans of the world.

The result is a 25.5 in. (65 cm) high and 40.5 in. (104 cm) wide pointillist artwork which – with some difficulty – you’ll be able to mount on your walls. The map is split into three sections, each focusing on a different landmass, so you can center the map on the Americas, Europe, or Asia.

2. Lego Icons Eiffel Tower

The tallest Lego set

Pros

• The largest Lego set you can build
• Gorgeous replica of a famous landmark

Cons

• As big as a modest Christmas tree
• Enthusiastic pets or children could destroy hours of work

The Lego Icons Eiffel Tower is utterly enormous, measuring 58 in. (149cm) to the tippy top of the French flag at the summit. Assembled in four sections, each as large as many other Lego builds, this kit is detailed at every level, from the esplanade at the feet of the tower to the observation galleries at the very top.

Ifwhat you want is size in your kit, you should check out our guide to the biggest Lego sets, where this – and the Lego Art World Map – have prominent positions.

3. Lego Technic Liebherr Crawler Crane LR 13000

Ultimate Lego engineering challenge

Pros

• Fully functional remote control crane
• App-based remote control

Cons

• Extremely expensive
• Absolutely huge
• Not as robust as a real crane for construction work

The Lego Technic Liebherr Crawler Crane LR 13000 is a massive build that pushes the limits of what’s possible with Technic. Like many other kits, the crawler crane contains a power block and app-controlled motors that power a set of caterpillar tracks, but the crane mounted on top of those trackstakes this to another level.

The crane can rotate through 360 degrees, and a complex combo of cables, pulleys, and motors allows you to raise and lower the crane’s boom, jib, and hook cable. Building this model is a genuine engineering challenge, and once you’re done you have a remote-controlled model that’s a genuine engineering vehicle.

4. Lego Super Mario 64 Question Mark Block

The most delicate Lego set

Pros

• Makes great decor when closed up
• Smoothly opens to reveal cute interior scenes
• A love letter to Mario

Cons

• Won’t survive heavy handling
• Small parts are easy to lose
• Hard to repair without complete disassembly

The Lego Super Mario 64 Question Mark Block is a true love letter to the Super Mario series. Once fully assembled it’s a shiny yellow recreation of the iconic blocks that Mario smashes with his head in his platformer series. Simply pressing certain panels will open up the block to reveal beautiful, micro-scale dioramas of Mario’s adventures in the Mushroom Kingdom.

The challenge here is the sheer delicacy of this piece. A hollow Lego cube is not a very strong construction, and you need to carefully assemble several dioramas and mount them into mechanisms built into the inside of that cube. The results are well worth it, though: one of these blocks has pride of place in Wargamer’s shared offices with the rest of Network N media.

5. Lego Creator Expert Taj Mahal

The most eye-watering Lego set

Pros

• Remarkably detailed
• A truly classy ornament

Cons

• Out of production
• Little variation in brick color

The Taj Mahal is a masterpiece of Indo-Islamic and world architecture, a building so visually distinctive that many people in the West don’t realize it’s a mausoleum, not a palace. The Lego Creator Expert Taj Mahalhas pride of placeat the top of our guide to the best Lego architecture setsandrecreates the iconic building in exacting detail.

It’s that verisimilitude that makes this Lego kit such a challenge. Almost every brick in this kit is off-white, with a tiny minority of other colors sprinkled in – blue, medium grey, dull yellow, bright yellow, and white. Like building a jigsaw puzzle where the picture is a pot of beans, you’re going to spend a very long time squinting at nearly identical pieces!

Have those daunting suggestions put you off the idea of a challenging build? Check out the best cheap Lego sets, the best Lego Ideas sets, and the best Lego dinosaurs, for some light-hearted alternatives.