He designed many iconic buildings, including:
* St. Paul's Cathedral: The most famous building he designed, and a masterpiece of English Baroque architecture.
* The Royal Observatory at Greenwich: A pivotal building for astronomy, it helped define the prime meridian.
* Hampton Court Palace: He contributed to the expansion and renovations of this grand palace.
* Chelsea Hospital: This building is still used today to care for retired soldiers.
* Many other churches and public buildings in London.
While he didn't author books, he did write extensively about his architectural theories and designs. These writings are valuable resources for understanding his work and the architectural styles of his time.