The most compelling reason to stop in Adjuntas lies 200m south of the plaza on PR-123, at c/Rodolfo González 30 – an innovative cultural and environmental centre known as Casa Pueblo (787/829-4842, http://www.casapueblo.org). The arresting pink criollo-style house was purchased in 1985 by a group of environmentalists that had already been protesting the development of local open-air copper mining for five years – the mining posed a catastrophic threat to the local ecosystem. It took fifteen years of campaigning, but in 1995 the government passed a bill prohibiting open-air mining in Puerto Rico, and by the following year the land formerly threatened by the mine was turned into a small reserve, the Bosque del Pueblo. Founder Alexis Massol-González received the prestigious Goldman Environmental Prize in 2002 on behalf of the group, and today Casa Pueblo supports sustainable development and conservation projects all over the island, also conducting a number of toxicity studies on Vieques.

The main house acts as a performance centre and art space, with a small shop selling local arts and crafts, coffee beans grown by the project (Café Madre Isla), T-shirts and books. Most of the wall space is dedicated to charting the group’s history and environmental campaigns through photographs and various media coverage. At the back is a small Mariposario (butterfly house) and garden, where caterpillars are reared on lettuce leaves. The whole place is powered by solar energy.