These Absolute Madmen Just Swam Into a Narrow, Wave-Filled Cave at Sunset Cliffs and Found Carved Stairs And Secret Tunnels From the Rum-Running Days

San Diego’s Sunset Cliffs Natural Park is already the kind of place where the views can kill you if you’re not paying attention. Soft sandstone bluffs that drop straight into the Pacific, unstable edges that have claimed more than a few people over the years, and an ocean that doesn’t mess around with rogue waves or surge. Now add a hidden sea cave that only opens up during the lowest of low tides, and you’ve got the kind of local secret that attracts exactly the type of person willing to wade, swim, and crawl through darkness for a look at some century-old carved stairs.

The footage shows one such explorer—a bald guy in a dark wetsuit—fighting through breaking waves right at the rocky entrance to the cave. Water is slamming the cliffs. He’s half-swimming, half-clinging to the rock face as whitewater crashes around him, then disappears into the pitch-black mouth of the cave. Inside, a flashlight beam cuts through the darkness. He’s climbing a series of rough, hand-carved or concrete-enhanced stairs that have been cut right into the rock. The passages are tight, wet, and uneven. He has to brace against the walls, duck low, and pick his way carefully across slick surfaces while the ocean continues to churn somewhere below or behind him. At one point, he turns the light on himself in a narrow squeeze, looking every bit like a guy who has decided this is worth it.

This is the cave locals have long called Rum Runners Cave or Smugglers Cave (sometimes Pirate’s Cave). It sits along the northern stretch of Sunset Cliffs, near what some refer to as Pappy’s Point. The system has two main entrances connected by an elevated narrow passageway through the rock. Concrete stairways give access to the upper sections. There are side passages, candle niches carved into the walls, and at least one longer corridor that runs closer to sea level and floods. One of those tunnels once continued toward the surface or a former structure; it has long since been filled in or sealed by the city. Accounts from people who have been inside describe wooden beams in places that look like they could have been used with ropes or simple pulleys to hoist cargo.

The story attached to the place is classic Prohibition-era California. From 1920 to 1933, the coast here was a drop point for illegal liquor. Larger ships sometimes sat just outside the three-mile limit. Smaller boats ran the cargo in at night. The cave’s layout, multiple entrances, stairs, elevated passages, and a path that once connected inland, fits the practical needs of moving bottles quickly and quietly. Some local accounts claim it was used by runners bringing alcohol from Mexico or offshore mother ships, with a tunnel leading toward a house or mansion on the bluff above. Other descriptions tie the man-made improvements (the stairs, enlarged passages) to earlier development around the 1915 Panama-California Exposition and the area’s old Spalding Park infrastructure, which the city later altered or buried. Either way, the physical evidence of human modification is real, and the timing lines up with the dry years when a lot of California’s coastline became unofficial ports of entry for Canadian whiskey, Caribbean rum, and whatever else people could move under the cover of darkness.

Access is brutal and strictly tide-dependent. You need a minus tide, ideally well below zero feet and preferably in the negative range during the winter months when those lows are more common. Even then it involves scrambling over wet, algae-slick rocks, possible swimming in places, and constant awareness of the swell. A wetsuit is the smart move. The water is colder and the surge is stronger than the more famous caves up the coast in La Jolla. The cliffs themselves are unstable—sections of sandstone and mudstone can and do fail. Signs warn about the edges. People have died here from falls, getting caught by rising water, or misjudging the ocean. The recommendation from anyone who has done it is simple: check the tide charts, go with other people, bring lights, watch the clock so you’re not still inside when the water starts coming back, and treat the whole thing as an adventure that can turn on you in minutes.

Sunset Cliffs has other sea caves, including a well-known open-ceiling one that draws photographers when the light is right. But this one, with its carved stairs, sealed tunnels, and direct link to the Prohibition rum-running trade that ran along Southern California’s coast, is the one with the better story. The video captures the current reality of getting in there: dark, wet, tight, and not for anyone who likes dry land or easy exits. The stairs are still there. The ocean still floods the lower passages. And every so often, when the tide drops low enough, someone still decides it’s worth swimming into the dark to see what’s left of the old smuggling route.