And he didn't miss the chance to make a political point with his latest feat. The submersible was launched Tuesday from the port of Sevastopol in Crimea -- Ukrainian territory that has been occupied by Russia for over a year
During his plunge below the surface of the Black Sea, Putin saw the recently discovered wreckage of a Byzantine ship on the seabed and spotted several centuries-old relics scattered around it, according to state-run RT.com.
His trip in the 3-man, glass-fronted vessel took him to a depth of 83 meters (272 feet), it said.
It's not the first time Putin has ventured beneath the waves.
In July 2013, he descended to the bottom of the Baltic Sea aboard a red submersible to explore a 19th-century shipwreck.
Putin climbed aboard an underwater research vessel for a 30-minute dive to the wooden wreck of the frigate Oleg, which sank in the Gulf of Finland in 1869. The site was discovered by divers in 2003.
Ukrainian President: Challenge to world
Putin's visit to the Crimean peninsula, which began Monday, has provoked anger in Kiev.
Ukrainian President Petro Poroshenko posted on his Facebook page that Putin's visit without the consent of the Ukrainian authorities "is a challenge to the civilized world" and meant to exacerbate the situation in eastern Ukraine, where conflict between pro-Russian separatists and Ukrainian forces continues despite a shaky ceasefire deal.
"Such visits mean further militarization of the occupied Ukrainian peninsula and increase its isolation," Poroshenko said, according to a translation by Ukraine's official Ukrinform news agency.
Asked about Poroshenko's remarks Tuesday, Putin told reporters the subject was closed, according to state news agency Sputnik.
"I am not going to make any comments on this issue, because the future of Crimea has been decided by people who live on this territory," Putin is quoted as saying. "They have voted for the reunification with Russia. Period."
Russia's Foreign Ministry said in a statement Tuesday that it was perplexed by Ukraine's response to the visit, Russian state news agency Tass reported.
"Visits by Russian officials to the Republic of Crimea and Sevastopol are the Russian Federation's purely internal affair," the statement reportedly said.
Putin is meeting with security officials in Crimea on Wednesday, Tass said.
The peninsula became part of the Soviet Union in 1917, following the Russian Revolution. But in 1991, following the breakup of the Soviet Union, it became part of a newly independent Ukraine.
On March 16, 2014, Crimea held a referendum on whether to continue as part of Ukraine or to cast its lot with the Russian Federation. The result was overwhelming, at least among those voting: 95% said they wanted to become part of Russia.
A mere two days later, Russia annexed the territory. Putin said later that he had been planning the move even before the referendum was held.
Before Crimea was formally absorbed by Russia, unidentified armed men had taken control of its administrative buildings and key military sites.
Kiev and Western nations consider Russia's annexation of Crimea illegal and have imposed a series of financial sanctions on Russian interests in response to Moscow's actions.