Explainer-Why Ukraine's southern Kherson region is a strategic prize

A local resident rides a bike near destroyed houses in the village of Arkhanhelske, Kherson region

KYIV (Reuters) - Ukrainian troops were greeted by joyous residents in the centre of Kherson on Friday after Russia abandoned the only regional capital it had captured since its invasion in February.

Russia said it had completed the pullout across the Dnipro River without losing a single soldier, but Ukrainians painted a picture of a chaotic retreat, with Russian troops ditching their uniforms or drowning while trying to escape.

Here is why the region is strategically important for the course of Russia's war in Ukraine.

GATEWAY TO CRIMEA

Kherson region borders Crimea and provides Moscow with a land bridge to the Black Sea peninsula that it seized from Kyiv in 2014. Ukraine retaking swathes of Kherson region would deprive Moscow of that land corridor. It would also bring long-range Ukrainian artillery closer to Crimea, which Moscow sees as vitally important to its interests.

The peninsula, whose annexation Putin sees as a key achievement of his more than two decades in power, is home to a huge Russian military force and the Black Sea Fleet, which Moscow uses to project power into the Mediterranean and the Middle East.

FRESH WATER SUPPLIES

Fresh water supply to Crimea would also be imperilled if Ukraine retakes Kherson region.

After Moscow seized Crimea, Kyiv blocked water supplies via a canal from the Dnipro. When Russia seized chunks of Kherson region and neighbouring Zaporizhzhia region to the east, it immediately moved to unblock the canal. Russia needs that water for the local population, the irrigation of the peninsula's arid land and for numerous military facilities.

LOGISTICS ROUTES

Kherson region includes the mouth of the wide Dnipro that bisects Ukraine. The regional capital, Kherson city, is on the west bank, across the river from most of the rest of the province. It was the only place where Russia had a presence on the west bank of the river and Russia had heavily reinforced its troops there in recent months.

Ukrainian forces hammered the bridges over the river to hurt Moscow's ability to resupply. If Russia were to lose its only foothold on the west side of the river, Ukraine would be better able to attack other Russian supply lines and challenge Moscow's grip on other occupied parts of the south, such as Zaporizhzhia region where Russian troops occupy a nuclear power plant.

"The right (west) bank is important for both sides - for (Russia) in order to ensure the steadiness of the defence of the Zaporizhzhia direction, and for (Ukraine) to free this direction and cut off these three important arteries: the land corridor to Crimea, the water to Crimea and to return control of the (nuclear plant)," said Oleh Zhdanov, a military analyst.

SYMBOLIC SIGNIFICANCE

The city of Kherson was the only regional capital that Russian forces captured since the Feb. 24 invasion. Losing it would therefore be a major symbolic blow to the Kremlin and indicate Russia had - for now - failed to press ahead to the cities of Mykolaiv and Odesa whose capture Moscow had sought, said Oleksander Musiyenko, a military analyst.

"It's clear the loss of Kherson and the Kherson bridgehead will have consequences for Russia's image and will be viewed negatively inside Russia," he said.

BLACK SEA CONTROL

The Kherson region, which had a pre-war population of more than 1 million, lies on the Black Sea. Recapturing it would help Kyiv wrest back control of some of the coastline along a sea that is a critical artery for its food exports to foreign markets.

(Reporting by Tom Balmforth, Pavel Polityuk; Editing by Gareth Jones, Tomasz Janowski, Peter Graff)