AMUDA, Syria -- Pummeled by modern U.S. weaponry, ISIS has been reduced to a single town – Baghoz. Now the cruel caliphate is surrounded by members of the Syrian defense force – predominantly Kurds – who say there are just days remaining. Brave, but light on equipment, they rely heavily on the U.S.

Fox News was granted rare access to the frontlines – to witness the final stand.

It’s a long and hard road to the far east of the country – through territory still being attacked by ISIS sleeper cells. After three days on the road, first traveling west from Iraq then south through Syria, we finally reached a SDF base in the Omar oil fields in what was once an ISIS heartland.

U.S. forces are everywhere here. You catch glimpses of them moving around, on the frontlines and in forward bases. U.S. mortar teams, intelligence, artillery and airstrikes are the reason the territorial caliphate was destroyed so quickly.

In one U.S. base, Fox News saw hundreds of troops and dozens of U.S. armored vehicles – a reminder of the scale of U.S involvement. There are said to be 2,000 U.S. troops here, but some believe the actual figure is higher.

The following day, in an SDF Humvee, we slowly pushed forward to the battlefield, bogged down by rain and mud.

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ISIS had years to dig into these towns, crisscrossing them with tunnels and littering them with IEDs. That has left the land obliterated. For miles, there is nothing but dead bodies and rubble.

ISIS now holds just over one-square mile of land, with about 1,500 to 2,000 fighters. The defiant ones who remain are mostly foreign fighters unable to blend back into the local population, and they’re making their final stand.

At their peak, ISIS controlled about 40,000 square miles, roughly an area the size of Kentucky. They had 65,000 fighters and ruled over 8 million people. Today, all of that is gone.

When President Trump took office, he told the military to take the gloves off against ISIS. Looking at the scale of U.S. artillery and airpower here, it’s clear that they have done just that.

Outside the final village far in the desert, by the Iraqi border, some ISIS fighters are still trying to escape, hoping to fight another day. Hidden among families, they flee into the surrounding desert, where they are swept up by the Kurds.

We watch as thousands of men women and children emerge from out of the desert fleeing the besieged fighting. They are split into men, women and children – and then the hunt is on to find which ones are ISIS. Many admit to being members of the terror group but say they were just cooks and cleaners – that they never wanted join, but had no choice, and never fought. SDF forces rarely believe them.

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Among them: ISIS brides. Most claim they were forced to join by their husbands. But their claim is highly doubted.

Their children have attended ISIS schools, indoctrinated from a young age, some have lived under the caliphate for five years. They are known as cubs of the caliphate – it’s a worrying sign for the future – and the big question here is what to do with them.

While ISIS may soon be defeated as a territorial force – what we’ve seen is an indication that many remain.

Arab villages nearby are no-go zones, and there are an estimated 20,000 ISIS followers still at large. Fox News learned a few days ago that the surrounded fighters had asked for safe passage to Turkey in exchange for a ceasefire – the SDF said no. They want these battle-hardened fighters finished off, and now.

It’s the geopolitics that also raises big questions. Once the caliphate falls, and the U.S. pulls out – as President Trump has suggested he’ll do – it’s widely expected that the Turks will move down across their border and attack the Kurds, who they see as terrorists.

And so, without U.S. support, the Kurds say they have no option but to talk to the Assad regime – they believe it’s the only way they’ll remain safe without the U.S. And as if to reiterate the point, just a mile from where we are, south of the frontlines, regime forces are waiting alongside Iranian militias – to move in once the U.S. leave.

The Kurds hope they can rely on the U.S. to offer continued support, and they urge the President to reconsider his decision to leave. They insist they’ve been long and trusted allies of the U.S., fought alongside them on numerous occasions, and lost thousands of men.

They also urge president Trump not to make the same mistake President Obama did, saying he left Iraq before the job was done – and handed that country to Iran.

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As we leave Syria, crossing the Euphrates back into Iraq, the feeling is that all we’ve witnessed is the end of one chapter. And there are many more to come.