Hidden among Rhode Island’s forests and coastlines, Thomas Dambo’s giant wooden trolls are turning heads and drawing crowds. Erik Rock – Ninigret ParkPhoto credit: Kailey MarcAurele. Erik Rock is one of the most popular and accessible trolls created by artist Thomas Dambo in Rhode Island. Located in Ninigret Park in Charlestown, this massive wooden sculpture offers a fun, family-friendly experience surrounded by nature. Greta Granite is hidden along the trails of Ninigret Park in Charlestown.