Jan Akkerman's group prior to joining Focus. There only album is rather dated mix of blues and psychedelia. Of note is the sixteen minute "Sea Of Delight", however, as it would blueprint many of Focus' longer compositions.
One of Holland's famous sons, Groep 1850 regrouped in 1968 in Amsterdam, recording two fantastically original psychedelic records, before disbanding on a regular basis. Even more exciting for the progressive fan was their final album, released in 1975.