We know what famous landmarks look like today, but iconic structures like the Statue of Liberty and the Sydney Opera House looked a bit different while they were being assembled.
While it only took a handful of months for Argentinians to erect the 221-foot Obelisco de Buenos Aires, which was built in 1936 to commemorate the 400th anniversary of the city's founding, other famous landmarks took longer.
The Sydney Opera House — whose iconic "shells" are covered in one million tiles and were built using cranes designed for the job — took 14 years and AU$ 102 million to complete, just in time for Queen Elizabeth II's visit to Australia in 1973.
Meanwhile, Antoni Gaudí's famous Sagrada Família in Barcelona, Spain, which features 18 ornate towers, stained-glass windows, and numerous ruled surfaces, has been a work in progress since 1882.
Here are photos that show the construction of monuments in cities around the world — and the end result.