# build castles in the air

idiom

Source: https://englishreference.com/idiom/build-castles-in-the-air
Updated: 2026-08-10

## Meaning

To have any desire, idea, or plan that is unlikely to be realized; to imagine visionary projects or schemes; to have an idle fancy or a pipe dream; to daydream.

## Examples

- Stop building castles in the air and focus on your real work.
- You are building castles in the air if you think this old car will fly.
- She builds castles in the air during every long meeting at the office.
- He spent all afternoon building castles in the air about winning the lottery instead of studying for his exams.
- My brother keeps building castles in the air about starting a tech company, but he has not even learned how to write code yet.
- Instead of building castles in the air about moving to a tropical island, we should save money for a small apartment in the city.
- While she often built castles in the air regarding her future career, she lacked the practical discipline required to turn those grand visions into reality.

## Origin

The first term dates from the late 1500s. A variant, castles in Spain (or châteaux en Espagne), was recorded in the Roman de la Rose in the 13th century and translated into English around 1365.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.