On: Barcelona’s Sagrada Familia will be completed in 2...

[rwmj]

Cathedrals (or technically in this case, a church) being built over decades or centuries is pretty common! This might be one of the quicker ones.

https://en.wikipedia.org/wiki/Cologne_Cathedral took six centuries, although they started and stopped a few times.

[boringg → rwmj]

Fair but those projects didn't happen during the 1900s where i would expect them to take long times for procurement and build.

[rwmj → boringg]

While it took less time (a mere 74 years) Liverpool Cathedral is an example of a long-running 1900s project.

https://en.wikipedia.org/wiki/Liverpool_Cathedral

[boringg → rwmj]

Great example. So with my qualifier Sagrada Familia might be the longest running modern day piece of construction.

Also Liverpool is one impressively sized cathedral.