It was much, much bigger than Rasputin's. By, at a conservative estimate, at least 1.2m.
Whereas few men would have readily shared a shower with the infamous Russian monk whose legendary lengthy manhood is preserved in a spaghetti jar in St Petersburg's "Erotic Museum", even less would go skinny-dipping with a whale. Whales are awesome creatures naked.
Iceland's "Phallological Museum" is the first and only one of its kind in the world. It is not good for a man's self-esteem. It is one of the most humiliating comparison sites you can visit.
Reykjavik's unique penis museum houses the largest collection of male genitalia ever collected under one roof by one man. The spare body parts storehouse boasts nearly 300 things taken from nearly 50 emasculated species. Fifty-five whale winkles are on display as well as 40 seal widgers. Ironically, there are no winkles' winkles.
The smallest object in the erogenous exhibition belongs, at 2mm, to a deceased but in life no doubt shamed-faced and not very body-confident hamster. It is close to being beyond micro-scopical resolution.
The biggest, weighing 69kg and measuring 170cm - and that's just the tip - was owned by a proud blue whale. The long-finned pilot whale has no reason to be shy either. A humpback would always keep the lights on.
I was greeted by a polar bear's fifth leg. And soon surrounded by wieners. And old chaps. Including one once attached to a Kawau Island wallaby. And another formerly part of a Wisconsin coyote.
The museum was opened in 1997 by 71-year-old Sigurdur Hjartarson, a retired teacher. He told me as a child he collected "pizzles".
"Puzzles?" I asked. He shook his head. "No. Pizzles. Bulls' penises."
He told me he used his first one as a whip. And that one of the exhibits has been converted into a walking stick. He collected his vital organs from local whaling stations and abattoirs as well as hunters. The only reproductive body part he has purchased is that of a late South African elephant.
"A meter," he remarked without me asking. Give or take a few centimetres." His eyebrows lifted. He admits he wants his male anatomy to look at its best. Some he cures. Some he pickles. Some he puts in formalin and formaldehyde. Some he mounts.
Members on show include a huge redfish (Ocean perch), a built bladder-nosed seal, a hung Swedish elk, a well-endowed Missouri bull, a just-about-to (thanks to the museum heating ) Arctic fox, a modestly endowed Ohio skunk, a not-so blessed fieldmouse, a shrivelled shrew, a dolphin with the droop, a sad German badger and an even sadder Mongolian gerbil.
Once you've seen one, you haven't seen them all.
"Watch your head," said my guide. I ducked under a killer whale's tackle jutting from the wall.
We passed a woman staring up at the meat and two veg of a Canadian walrus as if it were the Mona Lisa. Mr H also collects testicles and scrotums.
There was a queue for the magnifying glass to try to see the hamster. We stopped next in front of the embalmed bits and bobs of an American river otter. I made appreciative sounds.
The world's foremost penis collector presaged my questions. "Because someone had to. Because I'm a serious collector and phallology is an ancient science."
Sigurdur is fond of saying to visitors: "Collecting penises is no different from collecting anything else. You can never stop, never have enough and there's always a better, bigger, smaller, thicker or thinner one." He is also fond of wearing a phallocentric bow tie.
He is not fond of being asked which is his favourite. "I like them all. Usually the last is best" which is the recently acquired human schlong donated by Icelander Pall Arason who died at the age of 95. He is the only man in the world to expose himself posthumously on a daily basis. Some call the Reykjavik museum the local tool shop. And the city's best known hang-out.
No space is wasted. Penises, of varying shapes, sizes and degrees of shock-horror protrude from the wall. An hour-long tour is a real eye-opener.
If there is an afterlife I wouldn't mind coming back as porpoise. Or even a narwhal.
Getting there: Flights connect daily from London to Reykjavik.
Further information: The museum is open from 11am-6pm, daily at Laugavegur 116, Reykjavik.