Sagrada Família has been under continuous construction since ground was broken in 1882, making it one of the longest-running building projects still active anywhere in the world — and it remains an evolving building rather than a finished monument.
Why it's taken so long
The basilica was never publicly funded; construction has always been paid for through ticket sales and donations, which is part of why progress historically moved slowly compared with government-backed projects, especially during long funding gaps in the 20th century.
What's still being built
The central towers, including the tallest tower representing Jesus Christ, are among the last major elements still under construction, along with ongoing decorative work on the façades.
What this means for visitors
Because it's an active construction site, scaffolding and cranes are a normal part of the exterior view on any given visit, and specific areas can occasionally be closed off for work — it's worth checking the basilica's official site for any notices before you go.