Astronomy in the Canary Islands has grown from its historical beginnings at the site-testing expedition of C. Piazzi Smyth in 1856. Simony, Edgecomb, and Mascart followed in his footsteps. The Observatorio Astronomico del Teide was provisionally founded in 1959 to study the astronomical qualities of the Canary Islands' sky. It led to the present organisation of the Instituto de Astrofisica de Canarias and its two observatories on Teide and Roque de los Muchachos. This article gives a history of this process.