Hugh Hefner Laid to Rest in Private Ceremony with Kids, Crystal and Playboy Staffers

Hugh Hefner went to his final resting place Saturday, but only a select few of his closest friends and family were on hand for the ceremony ... TMZ has learned.

Our Playboy sources tell us ... Hef's 4 children, his wife Crystal Harris and some key Playboy staffers attended the funeral at L.A.'s Westwood Village Memorial Park Saturday at noon.

As we reported ... Hefner's crypt is directly to the left of Marilyn Monroe's -- he bought the burial spot for $75k in 1992. He'll have plenty of good company ... the cemetery is filled with celebs, many with Playboy ties.

One of the people buried in the cemetery -- around 100 feet from Hef's crypt -- is Dorothy Stratten, a Playboy Playmate who was murdered in 1980 by her estranged husband when she was just 20 years old. Her boyfriend at the time of her death, famed director Peter Bogdanovich, railed against Hefner, blaming him and the "Playboy sex factory" for her demise.