A network of trenches dug by Ukrainian volunteers is all that stands between the city of Mariupol and pro-Russian rebel forces who have taken over a nearby town.
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The elementary trenches look eerily similar to those most recently used in World War I.
The trenches were dug largely by volunteers and concerned citizens rather than the Ukrainian military, with concrete and sand bags helping to keep the underground barriers intact.
Tanks and soldiers from the Russia-backed insurgents have not yet made it to Mariupol, but residents fear that they are next since their port city is the next major town from Novoazovsk which was seized by the rebel forces last week.
Seizing the port city would give the pro-Russian forces - and consequently Russian access - to land route between Russia and Crimea, the oil-rich peninsula that Russia annexed from Ukraine earlier this year.