The nyckelharpa, a bowed instrument with keys, sympathetic and drone strings, dating from the 14th century at least, is featured in songs and instrumental pieces (scored also for violin, viola, and quinton d'amore) – a rich, remarkable timbre still at the heart of Sweden's musical tradition. The nyckelharpa (which resembles a violin with a keyboard of wooden keys), once widespread throughout northern Europe, has seen its range shrink as music has evolved, surviving only where it has been able to adapt. In Sweden, from the early 20th century onwards, traditional musicians, who until then had been confined to playing solo in a small area around their homes, began to meet up at folk events, spurred on by the Romantic wave sweeping across Europe. They were then confronted with other practices, other tonalities, and other repertoires. Even today, the nyckelharpa is still incredibly adaptable. Different research undertaken by instrument-makers and musicians are enlarging its sound range, and opening it up to classical or contemporary repertoire, jazz, and ancient music.