MOSUL -- This weekend, Iraqi forces backed by the U.S. military began what they hope will be the final push to drive ISIS out of the city of Mosul.

In an area in western Mosul, a region taken over by Iraqi forces not long ago, there are signs of what it costs to get rid of ISIS: The destruction is everywhere, staggering and it stretches on for miles. That is an ISIS car -- you can still see the decal there.

It's a combination of airstrikes, artillery, motars and of course ISIS suicide car bombs that have leveled buildings and cost the lives of hundreds of civilians.

In the western Mosul, there are signs everywhere of the cost of taking out ISIS. CBS News

Now over the past couple of days, there has been an uptick in the hostilities between both sides after the Iraqi forces announced a launch of a new offensive to take over the old city. Now we have three Iraqi forces coming from the south, the north and the west piutting the pinch on ISIS fighters who remain -- and they are pinned up against the Tigris River.

The Old City itself is densely populated and tightly packed with narrow roads and alleyways that make it difficult if not impossible for Iraqi forces' armoured vehicles or heavy equipment to get into. That means Iraqi forces are going to get to get out and fight

this battle on foot. And that gives ISIS something of an advantage. It also makes it much more difficult for U.S. airstrikes to pinpoint with great accuracy any of these suspected ISIS positions who are hiding among the residents of the in the civilan population here.

Iraqi commanders have said they know they are running out of time with an estimated 200,00 civilans still trapped inside the Old City. Their safety is of paramount imoprtance.