Premise: The Île de la Harpe is an island in Lake Geneva, located on the territory of the municipality of Rolle, in the canton of Vaud. It is an artificial island built in 1837. The island was named after the political leader Frédéric-César de La Harpe, after his death in 1838. An obelisk was built on the island in honour of de la Harpe.
Hypothesis: Many artificial islands were built in the 1830s.