My Hands-On Review of the new Lumibricks Alpine Observatory Set L9091

Hey brick fans!

As a die-hard fan who's already conquered and reviewed a handful of Lumibricks sets—like the stunning Steampunk Flying Club and the enchanting Bamboo House —I've been eagerly awaiting something that Lumibricks had yet to tackle, Space!. Enter the Lumibricks Alpine Observatory (Set L9091), a 2,437-piece lighted masterpiece that's elevated my collection to new heights (pun intended). While this observatory is terrestrially based, I can alternatively visualize it as serving as an outpost on some unknown planet, serving as some kind of far flung exploration base!

This mountain observatory has 4 different levels, rising from the rocky and snowy base, up to the glass enclosed research labs and amazing rotating observation telescope that functions as a projector of the night sky. Did you know that the Lumibricks set is inspired by the real-life Sphinx Observatory on Jungfraujoch in Switzerland?

If you're not familiar with the Lumibricks brand of Lego compatible sets, you'll find a plethora of printed parts in the Alpine Observatory (51 to be exact), and it's signature feature, the included lighting kit. The set features 13 lighting elements such as LED light dots and strips, including the galaxy light projector. And we can't forget the four Lumibricks style minifigures unique to this set. Thanks to Lumibricks for sending me this set to review, now let's take a closer look!

The set: Lumibricks Alpine Observatory L9091

Piece count: 2437 pcs

Minifigures: 4

Stickers: No

Printed parts: Yes, 51 of them

Lighting elements: Included, 13

Age Rating: 16+

Retail pricing:

Canada: 195.99 CAD Europe: 129.99 GBP USA: 173.99 USD

Black Friday and Cyber Monday Sale!

Get ready for the Lumibricks Black Friday and Cyber Monday. 📅 Mark your calendars and prepare to save big. During the Lumibricks Black Friday sale, you can save up to 30% off the sets on their website. This promotional event happens between November 20 thru December 1, 2025. Visit their website to see the newest sets in 2025!

Lumibricks is also available on Amazon!

Unboxing: A Box Full of Mountain Magic

Cracking open the box feels like unwrapping a gift from the cosmos—everything's sorted into numbered bags for a stress-free start, with the lighting components tucked safely in their own separate box.

Like all Lumibricks sets, they come in a sturdy premium box with lots of detailed information, even the manufacture date!

The set is jam packed with parts bags and two very thick instruction manuals.  Parts bags were numbered 1 through 14 and sequenced by the corresponding steps in the manuals.  Each step had their 3 or 4 respectively numbered bags.

The Lighting Kit

This is where Lumibricks really shines (yes, another pun).  Unlike Lego sets that don't come with any lighting, these included lighting kits are what makes Lumibricks sets so special.   Not only that, Lumibricks uses special bricks where you can hide the wires so the set interiors look very clean and tidy.

Here's what you get inside the lighting kit.  It includes two battery boxes but you'll need to provide your own 3 AA batteries (1.5V each) for the main lighting holder and 2 CR2032 coin cell batteries (3V each) for the projector.  The screwdriver is to remove the screws on the battery boxes. The tweezers are thoughtfully provided to manage lighting wires and smaller parts.  Other special components include 2 USB plugs, wireless connectors, expnsion boards and led strips and panels.  Bag 4 is special in that it contains the lens and 4 image disks that can be inserted into the projector, an extra is already included with the lens for a total of 5.

The Build: A Scenic Journey Up the Peak

As mentioned earlier, there are 14 steps to build the Alpine Observatory, and it took me about an hour for each step. Mind you ,I was also taking pictures of all the mesmerizing details along the way, so your build experience will be different than mine. It took me about 4 days building off and on following the manuals easy to follow instructions.

The first manual covered steps 1 through 6, and the second manual covered steps 7 through 14.

• Steps 1-2: The Foundation. 

 The foundation is constructed using several technic bricks assembled in a criss-cross fashion to provide strength and rigidity. It definitely provides solid support for the massive Alpine observatory.

Curved white bricks are mounted on their sides to create a snowy landscape.

• Steps 3–6: The Mountain Base.

Lots of cool little details hidden inside the mountain base.  There are the personnel quarters with two bunk beds, and a couple of workspaces.  Each one has their own lighting effect.  There's a ton of printed parts, especially a replica of the golden records that was sent out on the Voyager missions. And I love the snow covered rock formations !

The mountain base was fun to build and easily attached to the technic foundation.

• Steps 7-9: The Research Lab. 

Located above the personnel quarters, on the second floor, we find the research lab.  It's fully equipped with a science library, a computer workstation, a coffee maker and even a model of the solar system!  The lit up display of the universe big bang is out of this world!

On this step, you need to be careful when placing the wires in the walls, especially when seating the wireless connectors between the floors.  The swing out back panel wall, needs a bit of force to attach to the rest of the structure, but other than that no real issues here.

• Steps 10-11: The Monitoring Station.

The monitoring station is located on the third floor.  There's a few banks of electrical and scientific equipment, probably to operate the giant telescope mounted above.  There are multiple printed panels depicting various space images as part of the monitoring desk.  There's a large viewing platform around the outside of the monitoring level.   Again, I had to jiggle this section into place to make sure the wireless connections between the monitoring level and the research level made proper contact.

• Steps 12-14: The Rotating Telescope Dome and Finishing Touches

The telescopic projector dome rotates freely and you can open the doors to the telescope manually.  The projector led light is not that powerful and although Lumibricks gives you extra display cartridges, I didn't swap them out because  I was a bit lazy and didn't feel like taking apart the front of the telescope to change the images.

Lumibricks gives you a small battery case to attach and power the telescopic projector.  Since I didn't have any spare CR20232 batteries, I decided to connect the dome to the main power source using a 15 cm extension cable and swapping out the wire joiner on the second floor with a 4 port expansion board.  I connected all of the wires to the expansion board and attached the wire joiner at the back of the dome.

I got my 4 port expansion board and 15 cm extension wire from Lightailing.com.

And here's what the projector image looks like.  I had to put a white board about 12 inches away from the set to get a clear image.   I don't know why I have the dark blob above the picture though because I couldn't find any obstruction that would cause it.

The finishing touches to the Observatory include some cool features such as the lit up ceiling panel in the research station, the outdoor antenna array, the astrophotography camera, a flying bird and of course, the books with their pop culture reference to the Hitchhiker's Guide to the Galaxy!

Final Thoughts

I really really enjoyed building the  Lumibricks Alpine Observatory.  Things I liked were the lighting features, such as the large LED panels on the walls and ceiling (of course!), the jagged mountain terrain, all of the interior and exterior details with so many printed pieces.  

I was impressed by the overall aesthetic of the structure and design, but not only does the Observatory make a nice display piece, it's opening doors and panels at the rear of the building lends itself to a lot of play value.  Speaking of play value, we can't forget about the 4 unique minifigures that come with the set.

Although the set is designed as an Alpine Observatory, I can't help but think this would make a great off world research and exploration base on some far away planet.  I would love to set up some Star Wars minifigures and other space faring accessories to add to the set.

I truly appreciate that Lumibricks is willing to try new things, such as the incorporation of the projection feature into the set.  Hopefully they can continue to improve the feature in the future as I feel it is still a work in progress.  The image projection was satisfactory at close range but was very dim when displayed farther away.  Plus it was not very convenient to have to take apart the telescope in order to change the image discs.

Overall, I'd give this epic set a 4.8 out 5 rating.  It's a solid buy for anyone who likes space themed Lego sets or just something unique that Lego has never done before.

Don't forget to save up to 30% off all sets during the Lumibricks Black Friday sale starting November 20th!

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Let me know what you think of the set in the comments below and thanks for stopping by!

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