ARTICLES, SPEECHES AND OTHER READING
SEA CAVES AS I KNOW THEM
Smart kayakers are scared to death of sea caves. However, most of us -
full of abandon and void of common sense - find caverns filled with salt
water irresistible. Personally, I've never seen a sea cave I didn't enter -
and I've designed a kayak and traveled 10,000 miles to find them. When my
Asian sea cave survey was successful, I never went back - even to idyllic
I'm addicted to weird challenges, so I'm always looking for the longest,
smallest, most beautiful and complex sea caves I can find. I don't know of
anybody else who has studied or spent as much time exploring, logging,
surveying, playing and kayaking in sea caves. "Caveman's" caving adventures
were first brought to public light in the 1985 EMMY-Award winning
documentary, "Moloka'i's Forgotten Frontier". However, until this year,
there wasn't much print coverage on sea caving. I still haven't seen any
"deep" (i. e., totally dark) cave stories, but the interest is growing
enough that it is time for some safety pointers on how to enter sea caves in
At Sea Canoe, sea cave kayaking is science. South-East Asia's tropical
waters are filled with limestone islands, and limestone means caves. Unlike
the simple surf-battered sea caves of North America and volcanic Polynesia,
Asia's caves can extend for miles, with complex stalactite-filled
off-branches, high ceilings and low overhangs that open and close with the
If you paddle short, high, wide open caves in calm water, a decked
hard-shell is OK. However, I've found that for serious sea cave
explorations, an extra-tough inflatable is essential. In an inflatable, I
can lean from side to side, or lie down flat on the inflatable's floor and
inch under a low ceiling handhold by handhold. When surf fills one of those
"simple" caves with crashing foam that bounces your kayak off the rocks and
sucks you into a whirlpool, I'd just as soon have the inflatable's stability
and positive buoyancy.
Unfortunately, there aren't any stock inflatables tough enough to trust with
my life or my customers' welfare in dark, tight caverns filled with oysters
and jagged rocks. A year into my international explorations, I realized that
if I wanted a quality inflatable kayak that could do the crazy things I want
to do, I had to design it myself. Several years ago, Greg Ramp and I teamed
up to design the world's first self-bailing inflatable sea kayak. I needed a
kayak that is fast, stable, easy to operate, tough enough to surf over reefs
with expedition payload, low profile to minimize windage, etc.
Coincidentally, the same requirements work in caves.
Greg, now president of AIRE, Inc. is a true quality oriented craftsman, so I
asked him to modify AIRE's Sea Tiger for exploration work. We beefed up the
material and flattened the bottom to create Sea Canoe's signature model "Sea
Explorer" kayaks. Since then, "Sea Explorers" have logged more time in sea
caves than any other boat in the world.
Greg performed some electro-welding miracles, so the triple-layer Sea
Explorer is the toughest inflatable around. I can explore the darkest holes,
laying flat on my back inching my way into the unknown, in complete
confidence that I won't puncture the boat and take a swim in totally dark
unknown waters. (Some Fiberglass boys tried to follow us into an "easy" cave
once, and actually cut up their boats!)
Asia's caves are so weird I didn't stand a chance of developing the art of
"Tidal Sea Caving" without a decade of playing in Hawai'i's superb caves. (I
spent the 50's swimming and SCUBA diving into California kelp-filled caves,
which I now find so boring they don't even count.) Any open ocean cave has
special dangers. In intrusive dikes (wave battered fault lines that
eventually grow into sea caves) most dangers come from the element that
created the cave in the first place - surf. If you don't already know sea
caverns, never enter a cave if there's any wave surge, especially in a
hard-shell. A sea cave is like a rock garden, except the visibility isn't so
great. In even small swells, foam breaks against the cave walls, currents
bounce into each other, and the place is generally a mess. In a small cave,
confused waters automatically throw you into sharp rocks. If the cavern is
big, the eerie sound effects often panic the inexperienced.
If you keep a cool head, rough rides in sea caves are survivable even if
uncomfortable. Even with a strong dive light in an open cave, sound replaces
sight as your primary sense. When entering a cave, always listen behind you.
An unnoticeable swell on an open beach can create a six-foot crest deep down
inside that long funnel.
A "big" swell in the back of a 100 meter cave can be very exciting. Every
cave has its gurgling monster noises in the back, but a large block of water
plummeting into a narrowing cave sounds like a freight train coming at you.
It is a sound you never forget.
If you can still see sunlight in the mouth of the cave, watching doom
approach can be beautiful. When the water rises, that reassuring ray of
light becomes grotto torquoise. If it turns deep green, watch out - the wave
is unusually thick. You are going for a rocking chair ride in the dark that
may instantly throw you three meters straight up. Learn to "look up". I
always look for a high ceiling. Its scary back there, but the hydrodynamics
are similar paddling through surf. Of course, the wave still breaks in the
back of the cave - hopefully on a gravel beach. If you can keep your kayak
straight to the wave, you might not log roll. Stay away from the beach in
the back where the wave crests and breaks in the dark and you won't wipe
out. Find a spot with a high ceiling and you won't slam into the roof as the
wave passes by.
Turn into the wave as it comes It isn't essential to face it, but take the
wave straight on with either your bow or stern. Basically, you're riding
over forming waves. It just dark and narrow. Practise this routine in open
surf, inching your way slowly to the beach, feeling the waves form behind
you as you rock over their crests. It's much easier paddling out from the
beach with the waves before you - same inside the cave.
Unfortunately, Murphy's Law of Sea Cave surges says the blockbusters only
come when you are entering a cave, i. e., they are at your back. Whatever
you do, once you hear a wave coming, don't try to turn around to face it,
especially in an unfamiliar cave. It's almost impossible to "180" a kayak
rapidly inside a cave. The worst thing you can do is take the wave broadside
and log roll. Side-surfing is almost impossible in the dark. You'll probably
catch your bow or stern on a protruding rock anyway.
Surf kayakers knows the thrill of breaking through a cresting wave just as
it breaks. There's the thrill of going almost vertical as you power up the
face, the relief of punching through, and the report of going airborne and
slamming down on the back of the wave. The same dynamics occur at the back
of a sea cave, except you are in the dark and narrow. Combine the sound
effects, close and unfamiliar quarters, extremely vertical wave faces and
total darkness and you can feel free to insert "terror" for "thrill".
If I sound discouraging, I am. What is fun in open surf is life-threatening
in a sea cave. There's one small, long irresistible cave in Ha'upu Bay,
Moloka'i, a 100-metre narrow funnel just wide enough at the back to turn a
kayak around. Mrs. Murphy always sends an untimely swell just when I'm at
the back. Once, I was literally on the gravel beach, and foolishly tried to
turn the kayak around. I was dumped sideways. A few times I've powered up a
vertical face to punch through a cresting wave. These experiences were never
fun. If you do dump, fate rules. If you avoid eternal darkness, lucky
paddlers get spit onto a gravel beach without to any large rocks. You're
still alive, but it's a real mess getting you and a swamped boat out of
there before the next wave hits.
Some caves are really tunnels, open at both ends. Invariably, these guys are
big, with more light and less turbulence since the water doesn't back
pressure. Even so, I wouldn't want to be in the confused waters of
Moloka'i's "Jaws of Death" in anything but my Sea Explorer. Even in summer,
six-foot swells pile into its mouth, agitating the waters before you turn
inside the tunnel. One-meter haystacks crest two meters apart. In an
inflatable kayak, it's a fun ride, but I wouldn't want to go for a swim.
Surf creates lava and granite caves only as far as wave action penetrates.
Facing directly into Hawai'i famous ten-meter surf, tunnels on the North
Shores of Moloka'i and Na Pali are 150 meters at the most. In limestone,
less dramatic but constant tidal action creeps hundred of meters, in some
cases' kilometers, deep into the cliffs. Waves are still a problem at the
smaller entrances. However, where the brute force of water power is the
dominating factor in the Western Hemisphere, the subtle complexity of Asia's
limestone has its own set of dangers.
Beyond the openings of limestone caves, the water is always flat. However,
this flat water has its own set of dangers.
Many caves are merely entrances to inland tidal lagoons. In tropical Asia,
spring tides change as much as two feet an hour - an inch every two minutes.
Large volumes of water funnel through the caves, "boiling" over submerged
rocks and forming mid-stream whirlpools. The current moves as fast as a
mountain stream, complete with sound effects echoing off the cave walls. I
body surf Waimea Bay, but I could not swim in many of these caves.
Because the caves are so small, time inside the lagoons can be measured in
minutes, and only at precise tidal levels. Until a paddler learns a cave,
the kayak frequently bounces off submerged, irregular oyster encrusted
rocks. A stock inflatable is ribbons, hard-shells roll and a swimmer is
hamburger in these fast, dark rivers.
Limestone caves are noted for delicacy and complexity, and Asia's caves are
Some giant caverns have tiny "windows of opportunity", exact points on the
tide chart when a kayak can pass. In many cases, the kayak barely squeezes
through. We lean far to either side, or lay flat on our backs in the floor
of the Sea Explorers.
Like a mechanic on a "creeper", the Sea Canoe Team inches our way through
these windows, often with the roof mere inches over our noses.
We can see the rocks just above our eyes, but we feel our way into the
unknown, squeezing our reinforced bows into every small hole we can squeeze
into. This is no place to discuss the fine points of paddling rotation.
The body language is worth the effort. Beyond these small "windows", caverns
can be three-dimensional, with fifty meters ceilings, formed by chimney-like
"swallets", rainfall drainage tubes that run from the top of the island.
Frequently, a second "upstairs" cave parallels the sea cave. These
"over-under" caves formed a few thousand years ago when the sea was 3-5
meters higher. Frequently, the roof between the caves collapses. Stalactites
from one inch to thirty meters appear deep inside these sponge-like islands,
forming columns of crystallized sparkle in your flashlight beam.
It's a mystical wonderland. Sea Canoe's longest traverse to date is a three
kilometer cave that took 75 minutes each way. This Spring, we are going for
some caves in the Philippines with unknown endings. One is known to be five
miles long. In the Summer of '94, we explore more caves in Vietnam and New
Many of the longer limestone caves are entrances to cliff-lined inland tidal
lagoons, called "Hongs" in Thailand, which means "room". The largest inland
lagoons we know, in Vietnam, are up to two miles in diameter. These lagoons
hold vast amounts of water that funnels in and out of the caves with the
changing tides. Our Vietnamese guides tell us that fishermen swimming near
the entrances on rising tides are sucked into these caves. It isn't a
Some of Vietnam's lagoons are accessed by caves so large Vietnamese locals
paddle small boats into the lagoons. Others, especially in Thailand, are
served by smaller caves never entered before the Sea Explorer was invented.
The Magic inside these cylindrical enclaves is from a time before humans
walked the Earth. Discreet ecosystems develop, complete with natural
"bonsai" trees and gigantic shellfish.
Even after five years of Thailand explorations, the Sea Canoe Team is still
finding "hongs" (Thai for room). We are constantly working on new entries,
and expect to find more hongs in Thailand for years to come - especially if
the government every gets around to developing a permit system to protect
these pristine locations.
It isn't easy finding undiscovered sites in the late 20th Century. Our
survey techniques grow more sophisticated with experience, but we still
spend hours paddling down dead-end mangrove channels, or discovering hongs
with windows too small to access.
We often go swimming in the dark, feeling our way around the mud and
oysters, kicking underwater rocks, wondering if an avenue exists through the
rapid currents. My record was crawling down a gradually shrinking mud and
water-filled cave for 300 meters. One of our Thai partners and I entered the
cave walking upright. After 50 meters, we were on our hand and knees.
Finally, I stopped where my shoulders wedged between the narrow walls, and I
had to keep my face above water a foot deep. It wasn't easy slithering over
sharp rocks in mud-reverse until I could coil into a ball and turn around.
No sane person does these things, but that's the only way to find virgin
sites in today's world.
We aren't afraid to "pass" today, review our notes and return at another
time. More than once, prudent patience has saved my life. I surveyed one
giant cave in South Thailand that had to much water flowing at spring time
for my liking. A channel a meter deep and fifteen meters wide was flowing
into darkness so fast no person could swim against the current.
After a three day boat trip, the conditions just weren't right. I studied
the cave and decided on a possible entry level. Eighteen months later, the
water was flat for five hours at my predetermined level. We took that week
long round trip, only to find the cave's outside entrance collapsed. We took
an hour to portage over rock slides and through small access holes just to
reach the channel. Finally, we paddled into the dead still waters only to
come to a solid rock wall blocking the channel deep inside the cave, 20
meters wide at that point. The base of that solid rock wall is undercut at
least a meter from water slamming into it during spring tides.
Knowing the water had to get through somewhere, we found a small one
meter-wide oyster encrusted window. In the still water, we carefully picked
our way around the oysters. Any tidal change is magnified in this dramatic
funnel. It wouldn't be easy to gingerly inch our way past those oysters, not
to mention the rocks. Luckily, we didn't see it, but a spring tide obviously
sucks everything through that small hole with unmanageable speed and volume.
If I went for it that first time, I would not have been able to paddle, swim
or even stand against the current. If I survived the washing machine at the
base of that wall, I would have been sucked through those oysters - with the
water level a half-meter higher than the window. If I survived all that, cut
and hurt, I still had a two mile traverse of unknown darkness just to reach
daylight. Of course, daylight turned out to be an endless chain of
cliff-lined virgin hongs. I tried to access a Krabi province cave for
months. Since it sits behind a sand bank, we can't get our escort boat in at
low tide. Finally, I made the long paddle on my own, reaching the cave in
the middle of the tidal curve with the fast tide rising. I got 25 meters
further than anybody before me.
After months of surveys, my impatience got the best of me. I was breaking
all the rules and knew it. I was by myself a mile deep in mangrove swamps,
holding my paddle and the dive light in the same hand, the spring tide was
rising visibly, and there were oysters on the ceiling. This isn't a good
sign - overhead oysters mean the roof submerges at high tide. Before me, the
window was small and getting smaller as I watched. I decided to exit.
Reversing in the dark is never easy. On the spring tide, the cave's
configuration changed by the minute, and those overhead oysters were getting
closer and closer. The cave was too small to turn around, and I took longer
than expected reversing out. I finally reached the outside window so late I
had to exit my kayak to get out of the cave.
I was lucky to get out, but I knew from my observations when that window
opens. Working off our combined notes, Tom Sajan, an expedition lead guide,
finally accessed "Naporn" cave and Hong. It was a great thrill for Tom and
his guests, and I am alive to write about it.
Any reader of Mark Twain knows what happened to Tom Sawyer and Becky
Thatcher in a Missouri limestone cave. It isn't any different in Asia. Once
on a deep cave exploration, I took the sweep, giving staff the chance to
lead us through an especially long cave. Paddling mud-lined channels, we
came to a Y-junction. Surrounded by hundreds of sparkling columns, I knew
stalactite navigation was hopeless, so I settled on a strange shaped rock as
On our way out, Murphy's law guaranteed our new lead guides took us down the
wrong channel. Last in line, I watched as we passed my funny landmark rock.
Since we were exploring, I decided not to say anything - who needs a
navigational debate several kilometers inside a mountain. As expected, after
a few minutes, we literally came to a stone wall. Thanks to my landmark
rock, we weren't lost for days. After years of cave exploration, I know to
look for overhead oysters. I can judge a cave's access level at a glance;
know what to use for landmarks; and when to back off for another day. Sea
caving, either in surf beaten North America or Asia's tidal limestone
labyrinths, is a specialized and dangerous science. At Sea Canoe, we know
what to look for, and we don't take any chances, We always know there is
another day, even if we are thousands of miles from home. It might take a
year and a half to return, but when we do come back, it is on one piece and
with well-researched confidence. Fortunately, once we access a sea cave in
Polynesia or Asia, it's all clockwork from then on.
However, unless you understand the subtle nuances of sea caving by kayak, it
is better to be safe than sorry. Please, if you do enter caves, stay well
within your limits. The surprises are rapid. The consequences can be very
uncomfortable. However, if you enter sea caves with someone who knows them,
you see a mystically different and rewarding world. Just don't take any