Colombia has dramatically cut down its coca-leaf and cocaine production over the last decade, but it remains the largest supplier of the narcotic to the United States. This year along Colombia’s Pacific, more than 80 tons of cocaine has been seized, the Navy said.

While the submarine may be the most dramatic innovation, it’s not the only one.

Tucked between the vessels at the “museum” are what look like steel torpedoes — or what officials here call “unmanned submersibles.”

The torpedoes are streamlined containers that can carry several tons of cocaine and be towed behind an inconspicuous fishing vessel or attached to the hull of a boat. If the traffickers suspect they are about to be raided, they simply cut it loose.

“About a month ago, we noticed that they were starting to use electronic beacons on the unmanned submersibles,” Hernandez said. The technology allows smugglers to ditch their cargo and recover it days or weeks later.

Another recent innovation is the use of drop boxes that can be packed with cocaine and buried on a beach in, say, Costa Rica or Nicaragua.

“When the payment comes through, the client is given the coordinates of where to find the boxes,” Hernandez explained, “so there’s never a face-to-face meeting.”

As he peered into the hatch of one of the semisubmersibles, Lt. Diego Areiza described the drug war as a cat-and-mouse technology race.

“This is an example of the evolution of criminal innovation,” he said. “But it’s also an example of the way we’re evolving. Otherwise, you wouldn’t see all these vessels here.”

Capt. Ricardo Benitorevollo is a submariner in the Colombian Navy and has studied the narco-sub carefully. He said the machine has sophisticated submersion and trim controls, a ballast management system and central AC. When they discovered it, it was loaded with packages of caustic soda, suggesting the machine also was going to have an oxygen scrubber. He estimated it might cost $2 million to build.

Asked how it compared to Colombian subs, he said it was very similar to the Navy’s tactical sub but had more amenities. On the Colombian sub, officers have to go on deck to use the bathroom. The narco-sub has an interior bathroom.

There’s also another difference, he said: “Their beds are bigger.”

Miami Herald staff writer Carol Rosenberg contributed to this report from Miami.