Beginner
≈ 5 h 30 minSuggested range3 h 30 min – 8 h
Official LEGO® image · © LEGO Group and/or the respective rights holders. Source: LEGO Italy ↗
Ideas · SET 21321
International Space Station
A display ISS positions solar panels and a robotic arm beside small spacecraft.
- Pieces
- 864
- Release year
- 2020
- Theme
- Ideas
- Set number
- 21321
- LEGO recommended age
- 16+
- Launch retail price · Europe
- 69.99 €
Retired from the LEGO Italy catalogue when checked on 23 October 2026. Availability can change. Check the store for the latest information.
Retail price announced at launch for the stated market; not a current offer. Launch price source ↗ · Reference checked on 28 October 2026
Official English name verified at: LEGO English catalogue ↗ · Checked on 24 October 2026.
TIME TO BUILD
How long does it take to build International Space Station?
A starting point for planning your build. Times for each experience level are editorial estimates, not measurements submitted by HowLongToBuild users.
Editorial model estimate · no verified measured building time
Intermediate
≈ 3 h 45 minSuggested range2 h 15 min – 5 h 30 minExperienced
≈ 2 h 45 minSuggested range1 h 45 min – 4 hBased on one person building the set for the first time, following the original instructions and using numbered bags where supplied. Includes normal piece-finding and minor adjustments; excludes long breaks, filming, dismantling and modifications. Sources may use different methods. This range is neither a statistical interval nor a limit: your build may take less or more time.
How we estimate times · sources and method
A slender structure, numerous repeated panels and delicate connections. The three central durations are model-specific editorial assessments. Planning ranges extend approximately from 65% to 145%, rounded to quarter-hours; they are not measured experience-level averages or guaranteed limits.
Sources do not always specify the builder’s experience. The three experience bands are our editorial assessment, based on the complexity of the set and individual accounts where available.
- LEGO Italy · International Space Station ↗
This source documents the model’s features and components, not a timed build. No sufficiently verifiable individual building-time report has been identified for this set.
- LEGO building instructions · International Space Station ↗
Set-specific instructions checked against the set number, piece count and year. The duration is an editorial assessment based on piece count, construction type, mechanisms and detail.
Checked: 23 ottobre 2026 · Method v1.0 · Limited reports; not a statistical average.
BUILT BY THE COMMUNITY
Yours could be the first building time.
0 reviewed solo building times.
No solo building times have been reviewed yet. You can still find editorial estimates under Suggested times.
Log your buildBuild your own story.
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Create a free account →BEYOND THE BRICKS
Did you know?
Inside the set
Eight adjustable panels
Two rotating joints orient the solar-array groups.
LEGO sourceAn articulated Canadarm2
The buildable arm accompanies a shuttle and three small cargo craft.
LEGO sourceBeyond the set
The stories, places and inventions behind your build.
A station assembled over time
The first ISS elements reached orbit in 1998, following Shuttle-Mir cooperation. Components launched at different times were joined to build the station.
Read the full story
Thinking of it as an orbital construction site helps explain its modules and connections: it was not sent into space as one finished building.
Cooperation built into the hardware
NASA, Roscosmos, ESA, JAXA and the Canadian Space Agency share the ISS partnership, with responsibilities for their systems and components.
Read the full story
Cooperation is operational and technical, not just a matter of astronaut nationalities. The laboratory’s physical form reflects contributions that must function together in orbit.
A CLOSER LOOK
Two modules that first met in orbit
When Unity joined Zarya on 6 December 1998, the two elements had never even been together in the same hemisphere on Earth. They were connected in space during STS-88, with help from shuttle Endeavour’s robotic arm.
Read the full story
Matching two cylinders was not enough: Unity had to distribute resources and connect future living spaces. NASA describes over 50,000 mechanical items, 216 fluid and gas lines and extensive cabling. Behind the station’s silhouette lies a story of interfaces engineered to work at their first meeting.
A CLOSER LOOK
Power has to last through darkness
The International Space Station’s solar arrays cannot generate electricity in Earth’s shadow. Batteries allow its systems and experiments to keep operating.
Read the full story
A 2015 NASA account explained that, in sunlight, roughly 60% of generated power charged the batteries. That figure describes the historical configuration, not a measurement of today’s station.
Expanded stories updated on 29 October 2026
Written by HowLongToBuild · Sources are linked with each story · Checked on 23 October 2026. Historical facts and story details refer to the context described.
THE COMMUNITY’S EXPERIENCE
What was it like to build?
Three separate scores from 1 to 10. For difficulty, 1 means very easy and 10 means very difficult.
No approved ratings yet. Scores are never generated by this site or inferred from the recommended age.
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Specific steps, useful checks and sticking points. Contributions appear after moderation, in their original language. Do not upload instruction pages or personal contact details.
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Sign in to contributeSET THE MOOD
A soundtrack for your build
· A pairing for this model
Suspended musical spaces and a sense of distance accompany missions, structures and cosmic landscapes. Apollo suits exploration and patient sessions, with curiosity and wonder.
OUR PICK
Apollo: Atmospheres and Soundtracks (Extended Edition)
Brian Eno, Daniel Lanois & Roger Eno
Intimate and spaciousEditorial suggestions, not official soundtracks for the set. External services may require an account or subscription; editions and availability can vary by country. Suggest another soundtrack →
Report a problem with this set →
YOUR NEXT BUILD
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