In the final centuries before contact with the Spaniards, the Tairona heartland in the Sierra Nevada de Santa Marta was densely populated. In the last years many archaeological sites have been discovered, ranging from small settlements to large towns. The Tairona also constructed irrigation canals and agricultural terraces for maize and a variety of other crops, and their skill as engineers and architects is attested by the stone roads, reservoirs, bridges and stairways. They also excelled in goldwork which combines a technical mastery of casting with a love of fine detail. Instead of a few impressive ornaments worn by a few chiefs large quantities of adornments were also available to a large proportion of the population.