Bristol City Council is redesigning the road layout near Temple Meads railway station.
It is expected that the work won't be finished until at least Autumn 2018.
Work starts today to redevelop the Temple Gate roundabout.
Anyone who drives through Bristol knows how busy the roundabout can get.
It's right next to Temple Meads train station, and is a junction for almost every major route leading in and out of the city.
"It's certainly going to be regarded as a major pain by Bristol motorists. They feel as if they often get the brunt of the roadworks, but what we would urge them to understand is that this is about short-term pain for long-term gain."
The Southern section of the Temple Gate Roundabout will be closed until Autumn 2018.
The redevelopment of Temple Quay is at the forefront of the plans, but the main goal is to ease traffic disruption in one of the most congested in the country.
"We've delayed the start of these so that they come after the works that were happening in the centre. So, we will make it as un-intrusive as possible."
For those that have been caught in the congestion, this is the start of essential works to regenerate a struggling part of the city
For others it's yet another barrier to Bristol's traffic flow