I feel that I've done Easter Island, the Voynich Manuscript, the final resting place of Amelia Earhart . . . If the Nazis designed a "bell-shaped anti-gravity machine" in Poland's Wenceslas Mine, what a dog it must have been. And those online pictures don't look much to me like a "human face on Mars" - or "a pyramid in Antarctica" ... But it pays to keep an open mind.
For example, the "Tunguska Event" - a huge explosion which flattened 2000 square kilometres of remote Siberian forest in 1908 - is now been explained by an asteroid or comet striking the atmosphere. But this mystery had scientists scratching their heads for decades.
While not claiming to have found anything quite as splendid, here - just for your summer reading pleasure - I've jotted down some favourite Kiwi mysteries:
Lost petroglyph of Baldrock
Baldrock is a spooky looking hill, actually a closed quarry, just off State Highway 1 about 5km north of the Lower Northland town of Kaiwaka. This was one of the sites which figured in Te Ika-A-Ranganui, the route of Ngati Whatua locals by Hongi Heke and his men in 1825. This chilling Musket Wars massacre accounted for more than at 1000 victims. Baldrock - now closed to the public - has had an unusual rock carving but it hasn't been seen for about 100 years.
A fighting chief is supposed to have made his last stand here, hiding a valuable mere (some say in a cave, others by throwing it away) just before he was killed. Sounds to me like something borrowed from the Arthurian Legend, but the rock carving (pictured) really was there because a photograph exists. A few years ago I scoured the rock with an elderly Kaiwaka resident in the vain attempt to re-discover it. We marched right up to the boulder where it was supposedly once chiselled, but not a sign remained.
The Kaimanawa wall
A structure in the Kaimanawa Forest Park, which resembles a giant man-made stack of stones, created a sensation when it was discovered in 1996.
For a few weeks this became "the smoking gun" to prove existence of the fabled Waitaha Nation, a mythical white-skinned people said to have arrived in New Zealand 2000 years ago, only to be wiped out 700-800 years ago by later-arriving Maori.
But a DOC geologist found the structure was merely an outcrop of 330,000 volcanic rock, of a type common elsewhere in Taupo's volcanic zone.
Similar fractures, resembling symmetrical blockwork, can be seen elsewhere in the district, he pointed out. But regardless of who or what made it, if you're passing by the "wall", it's well worth stopping to take a selfie.
The Great Barrier 'giants'
I still don't know what to make of this "mystery", delivered to me over a couple of beers at Great Barrier Lodge a few years back.
To me the local legend is reminiscent of the 1643 fable that Abel Tasman and his crew discovered giants on the Three Kings Islands.
The, um, long-and-short of it is that some locals reported giant human bones had been found years back, and that giants once inhabited the island. Though the claims seemed interesting I found no facts with which to corroborate them.
The only "evidence" was a collection of ancient weapons and hand tools, which is held on the island. But the owner, though confirming some seemed "pretty big", declined to have them examined. Meanwhile, an academic pointed out sensibly that even if a giant human skeleton had been found on the island years ago, this would hardly prove that an entire community of the big people once lived there.
In the historic sense, this one is possibly the greatest mystery recorded here, but probably also the one least likely to be solved. All we know is that when Frederick Hasselborough, the man credited with discovering this wind-swept penguin colony, arrived in 1810, he was not the first. Apparently a man-of-few-words, Hasselborough noted in his log that when he arrived "a ship of ancient design" was already on the island. Was it Dutch, Polynesian, Chinese? If the ship is ever identified, it could rewrite history.
Some enthusiasts maintain it was a Ming Dynasty treasure ship, dating from the 15th Century, though this seems unlikely.
We may never know the ship's nationality, as over the years sealers sent to the island used the wreck for firewood.
Yet, clearly, sailors unknown got within cooee of Antarctica, well ahead of the Napoleonic-era sea captain credited with discovering Macquarie Island.
By the way New Zealanders ran a penguin oil factory on the island many years before the Aussies established their weather station there.
Many folk have heard about the 1000 tonne US-registered barque which sailed into an enormous sea cave on Auckland Island, and wrecked there in 1864. Sixty eight lives were lost in the wreck, plus a cargo said to include 2,576 ounces (73 kg) of gold.
Ten who survived the disaster were rescued from the island in 1867.
Numerous salvage expeditions - some ending in tragedy - have failed to locate the ship and its valuable cargo.
If fact, no wreckage from the General Grant has even been positively identified. Even more mysteriously, the sea cave in which survivors said she broke up also seems to have disappeared. Some experts say that the giant cave must have, err, caved-in.
The Lady of Campbell Island
There's been plenty written about a female castaway said to have lived and died alone on Campbell Island circa 1820.
DOC even plans to conserve the site of the so-called "Lady of the Heather Hut", at Camp Cove. Experts are to examine it this year, though conservation efforts - including construction of a fence to keep sea lions away and removal of scrub - have now been delayed till next year.
The story goes that the woman, dubbed "The Lady of the Heather" was descended from Bonnie Prince Charlie, and was banished to New Zealand for political reasons.
It is said that her hut had lace curtains, a pebble path leading down to the water and a garden of heather nearby. The woman, who wore Stuart tartans, may have been one of the female ex-convicts who accompanied sealers to the island. Some reports say she was interred in a grave that is near the hut.
The Scotsman newspaper is taking an active interest in this story.