By the late 1960s , referred to as the `` golden age '' or `` classic rock '' period , a number of distinct rock music sub-genres had emerged , including hybrids like blues rock , folk rock , country rock , and jazz-rock fusion , many of which contributed to the development of psychedelic rock , which was influenced by the countercultural psychedelic scene .
These included hybrids like blues rock , folk rock , country rock , and jazz-rock fusion .