This is the fourth stage of the event and 124 of the world's best riders are on the roads.
The route is 165 kilometres long and started in Mansfield's town centre at 11:00 and is set to finish in Newark-on-Trent at 15:20.
The riders will be racing through rolling hills, market towns and quaint villages.
There are four sprint areas on the route, based in Mansfield, Collingham, Bilsthorpe and Ranskill.
The riders will be battling for the 'King Of The Mountains' jersey at Eaton Wood, near Retford, as they put their climbing skills to the test.
Caleb Ewan went into the start of the day at the top of the rankings.