These Are 14 of the Most Challenging Lego Sets To Build

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In the 90 years since they were invented in Denmark, Lego bricks have been used to bring countless scenes to life in homes around the globe. From licensed pop culture-inspired sets like “Star Wars” and Harry Potter to buildings dreamed up by amateur architects, there are an endless number of things to assemble.

While building Lego sets may seem easy enough, especially with the instructions provided in each box, the labor it takes to build some of the company’s sets can take hours — even days.

Listed here are what we consider to be some of the most challenging Lego sets to build. When defining what is the most challenging, we took what the set is, how many pieces it has and its suggested level of difficulty into consideration.

1. ‘Star Wars’ Ultimate Millennium Falcon (7,541 pieces)

Any “Star Wars” fan and Lego expert would love to have this epic set in their collection. The Ultimate Millennium Falcon comes with more than 7,500 pieces and is recommended for builders ages 16 and up. It has a lowering boarding ramp, a concealed blaster cannon and comes with seven minifigures that span the history of that beloved ship.


2. ‘Star Wars: A New Hope’ Imperial Star Destroyer (4,784 pieces)

Keeping on the “Star Wars” theme, this Imperial Star Destroyer kit is also part of Lego’s Ultimate Collector Series. It boasts nearly 5,000 pieces and measures more than 3 1/2 feet in length when completed! It also comes with a display stand and a pair of Imperial minifigures. Of course, the impressive set comes with a premium price tag of nearly $700.


3. Lego Creator Expert Taj Mahal (5,923 pieces)

With nearly 6,000 pieces, this Lego Creator model of India’s Taj Mahal is recommended only for the most advanced Lego builders. The finished product is full of ornate details on the inside and out and will measure at 16 inches tall by 20 inches wide. Like the other expert-rated Lego sets, this one is recommended only for builders ages 16 and up.


4. Lego Creator Expert Tower Bridge (4,295 pieces)

Another geographical model from the Lego Creator line makes our list, as this set represents London’s iconic Tower Bridge. The bridge is more than 3 feet long when it’s all built and the center bridge platform itself actually raises and lowers like the real one. It comes with four different vehicles you might see crossing the bridge, such as a red double-decker bus.


5. Lego Creator Expert Carousel (2,670 pieces)

Once it’s completed, this epic carousel actually spins while the animal-shaped cars move up and down when you turn the crank. The kit comes with seven minifigures, including a family and a ride operator, which help set the scene once your building is done. The Lego Creator Expert Carousel set also comes with accessories like candy, hot dogs and ice cream for your minifigs to hold.


6. ‘Star Wars’ Sandcrawler (3,296 pieces)

Unlike most of the other kits included in our list, this one is graded for kids as young as 14 years old. The massive Sandcrawler vehicle from “Star Wars” is 1 1/2 feet long once you’ve put together its more than 3,200 pieces. The seven minifigures it comes with are a dream for fans of the sci-fi saga, as they include icons like Luke Skywalker, C-3PO and R2-D2.


7. Harry Potter Hogwarts Castle (6,020 pieces)

Lego has rolled out some impressive Harry Potter-themed kits in recent years but this Hogwarts Castle one is the most epic. It boasts more than 6,000 pieces which come together to create a 27-inch wide replica of the world’s most famous school for witchcraft and wizardry. Minifigures of the four founders of the Hogwarts houses are included, along with a host of accessories.


8. ‘Star Wars’ Death Star (3,803 pieces)

Yet another difficult Lego set for “Star Wars” lovers is this replica of the Death Star. Since this set is an open circle, it is different from your typical Lego models, making it more difficult to build. This now-discontinued set comes with a whopping 24 minifigures with virtually all your favorite heroes and villains from the original trilogy.


9. Lego Creator Expert Roller Coaster (4,124 pieces)

This impressive kit was a winner at the Toy of the Year Awards in 2019. It includes more than 4,000 pieces and ends up being a fully working roller coaster that runs via a hand-operated crank or using a Lego Power Functions tool. The Lego Creator Expert Roller Coaster set also comes with 11 minifigures, a smoothie stand and a cotton candy cart for more immersion.


10. Lego Creator Expert Sydney Opera House (2,989 pieces)

This Lego replica of the Australian landmark might not have as many pieces as some of the other sets on this list, but with the pieces only being two main colors, it can get complicated to keep them straight. The model will end up being more than 2 feet wide once it’s built and will make an impressive conversation starter once it’s on display. Lego says the construction of this one is so sturdy that it can easily be moved without ruining your hard work.


11. Lego Creator Expert Old Trafford — Manchester United (3,898 pieces)

If you know someone who loves Lego as much as they love soccer, this difficult set will keep them busy. It’s a Lego Creator Expert model of Old Trafford, the famous stadium that’s home to England’s Manchester United. The detailed set includes details that make this a perfect showpiece for the home or office, including a statue of Sir Alex Ferguson.


12. Marvel Super Heroes The SHIELD Helicarrier (2,996 pieces)

This detailed Lego set inspired by Marvel’s Avengers series contains minifigures such as Captain America and Black Widow, two runways and three fighter jets. The SHIELD Helicarrier in this kit will end up being 31 inches long when it’s all put together. With nearly 3,000 pieces in total, it will take a hero to keep everything in order while building.


13. Lego Ideas Grand Piano (3,662 pieces)

Lego has really come up with some amazing sets over the years and this 2021 winner at the Toy of the Year Awards has to be one of the most intricate. This Lego Ideas Grand Piano set is so advanced, it’s only recommended for adults, with the minimum age listed as 18 years old. Once you’re done putting its 3,662 pieces together, you’re left with a 12-inch wide grand piano that has 25 playable keys.


14. Lego Creator Expert Colosseum (9,036 pieces)

All the sets we’ve featured in this list are massive but this Lego Creator Expert Colosseum has more than three times the amount of pieces of some of them! As of November 2020, this was the biggest set ever created by Lego, making it possibly the ultimate challenge for lovers of the brick. This one is also recommended only for builders that are at least 18 years old and results in a replica of the Italian icon that is nearly 2 feet deep.