ODESSA, Ukraine—Sparks fly day and night at the rail yard of Odessa’s tram authority, where men in coveralls are slicing up old steel rails and welding them into barricades called “hedgehogs” to stop Russian tanks.
Not far away, the area around the city’s elegant baroque opera house looks like a set from a World War II movie, with chest-high stacks of sandbags and troops in green uniforms. And a food market downtown popular with hipsters has been turned into a warehouse for a range of provisions — food, clothing and medicine for the troops.
A major attack on Odessa, which as Ukraine’s biggest port city is crucial for the country’s economic survival, feels like an inevitability, officials and residents say.
Russian naval ships have gathered just outside Ukraine’s territorial waters in the Black Sea, and Russian troops are pushing ever closer from the east. On Wednesday, the city’s mayor, Gennady Trukhanov was inspecting a bomb shelter at an orphanage when he received a call that a Russian jet, likely having flown in from the Crimean Peninsula, had fired a rocket at a military installation just outside town.
“Do you have your diaper on?” the mayor asked the person he was speaking with, laughing. “Don’t be a hero, there will be time for that later,” he said.
“I think they’re testing our antiaircraft systems,” Mr. Trukhanov said when he hung up the phone. “He flies in, we open fire, he flies away and almost immediately they fire a rocket.”
For the first several days of the invasion, Russia primarily concentrated its military forces on Kyiv, in the north, and Ukraine’s second-largest city, Kharkiv, in the northeast. But a concerted and in many ways more successful campaign is being waged in Ukraine’s south, along the coasts of the Black Sea and the Sea of Azov, a small, important body of water where Russia seeks full control.
As of Wednesday, Russian forces had captured the strategically important city of Kherson at the mouth of the Dnieper River, the first major city to come under Russian control. The fate of Mariupol on the Sea of Azov, an inland body of water that Russia and Ukraine share, also hung in the balance as Russian naval forces gathered in an apparent effort to mount an amphibious attack.
The carnage in Kherson was particularly extreme: Volunteers had been dispatched to gather up bodies, many of them unidentifiable because of tank and artillery fire, and bury them in mass graves, the city’s mayor, Igor Kolykhaev, said in an interview on Wednesday.
“They’ve fully come into the city,” Mr. Kolykhaev said, adding that he met with the Russian commander, who said he intended to put in place a military administration.
Kherson, with a population of around 300,000, is just over 120 miles from Odessa, and Russian troops have already pushed beyond it to Mykolaiv, about 45 miles to the north, Ukrainian officials said.
But it is Odessa that would be the real prize. Founded by Catherine the Great in the late 1700s, the city was a crown jewel of the Russian Empire and a critical commercial port for the Soviet Union. Though not as militarily significant as the Crimean Peninsula, which Russia annexed in 2014, President Vladimir V. Putin of Russia has spoken wistfully about the reconstitution of imperial-era New Russia, a region along the Black Sea centered on Odessa.
Like the eastern regions of Donetsk and Luhansk, Odessa was the site of a separatist uprising backed by Russia in 2014 that sought to create an independent state. But the effort was crushed after a series of pitched street battles pitting the separatists against Ukrainian nationalists and soccer hooligans, which culminated in the torching of a trade union building on the outskirts of Odessa. At least 40 pro-Russian activists were killed.
Days before the invasion started last week, Mr. Putin issued a threat against those who started the fire, suggesting that Odessa was on his mind.
“The criminals who committed this evil act have not been punished,” he said. “No one is looking for them, but we know them by name.”
Mr. Trukhanov, the Odessa mayor, backed by assessments from Ukraine’s military, said Russia’s goal was likely to surround Odessa with land and naval forces, cutting off Ukraine’s access to the Black Sea, which is the country’s primary link to the global economy.
Surrounding Odessa, he said, “will put an end to cargo shipments, an end to the economy and the end of development.”
He added, “But we’re not talking about that often, because the priority is survival.”
Odessa has undergone a profound and disturbing transformation since Russia invaded. Just over a week ago, the city was experiencing an unusual early warm snap that drove people outside, to the city’s cobblestone streets and beaches. Crowds flocked to the opera house, flamboyantly renovated with polished marble and 25 pounds of gold leaf, to see a performance of Madama Butterfly.
Now the entire, historic center around the opera is sealed off by sandbags, barbed wire and troops armed with automatic weapons.
“I can’t believe that a week ago I was a lawyer,” said Inga Kordynovska. She said he had been planning to compete in an international ballroom dancing competition, but was now coordinating the collection of food, clothing and medicine for Odessa’s territorial defense troops.
“One day, I had heels and makeup; I was going to ballroom dancing,” she said “And now everything has changed.”
The entrance to the Odessa Food Market has been draped with a large Red Cross banner and fortified with sandbags. Before the war, people used to eat Chinese street food and sip craft IPAs; now men in beanie hats and neck tattoos are stacking bottles of water and sorting bags of clothing.
Though the mission is to gather supplies for the city’s defenders, none of the combatants are allowed to enter the hall, said Nikolai Viknianskyi, who owns a furniture company and is now volunteering at the site.
“We’ve banned people with weapons from coming here so as not to attract other people with weapons,” Mr. Viknianskyi. “We don’t want for our hipsters or our fashionable youth to be hurt. They’re not military people, they don’t know how to fight.”
The fight may come anyway. As if to underscore the threat, Ukraine’s president, Volodymyr Zelenksy, replaced the Odessa region’s civilian governor with a colonel from Ukraine’s armed forces. On Wednesday, Ukraine’s Navy accused Russian forces in the Black Sea of attempting to enter Ukraine’s territorial waters using civilian boats as a “human shield.”
Though Odessa has not experienced the intense shelling of other cities like Kyiv and Kharkiv, there have been sporadic rocket attacks. It was unclear if Wednesday’s hostilities caused any injuries, but one person was killed on Tuesday in an attack on a military radar installation, Mr. Trukhanov, the Odessa mayor, said.
Also on Tuesday, an explosion ripped through the small village of Dachne, north of Odessa just off the highway to Kyiv. Several houses along a potholed street were reduced to rubble, and power line poles and trees were snapped at their bases.
A 60-year-old resident named Yuri said workers had extracted an undetonated shell from his front yard, which destroyed a brand-new Volkswagen his children had given him for his birthday. It was not clear whether the shell was fired by Russian forces or if Ukrainian troops mistakenly hit the village.
All this has rattled the residents of Odessa. At an orphanage visited by Mr. Trukhanov on Wednesday, tiny jackets had been arranged on a table to be ready in case the children have to make a dash to the bomb shelter in the basement.
After lunch time, a group of the youngest was tucked into their beds for nap time, while their caretaker stood over them, playing a lullaby on her phone, and silently crying.
“God,” she said, addressing the mayor, “everything is going to be OK, right?”