When: Wednesday, September 14, 2011

Start: Welshpool

Finish: Caerphilly

Distance: 183.7km

ITV4 highlights: 8-9pm

The general classification is likely to get another shake-up after stage four, which features two first-category climbs as well as several short and sharp tests along the 183.7km route.

The race reaches its highest point when it scales the Brecon Beacons 126km in, although the racing should come alive on the Caerphilly Mountain, which comes just five kilometres from the finish.

With its 12 per cent sections we’re likely to see several attacks on the ascent before those left behind will have to be fearless on the descent into the finish.

Even if this stage changes little on the GC, the battle for the victory in Caerphilly should be fascinating.

Stage 4 profile, Tour of Britain 2011

Stage 4 map, Tour of Britain 2011

Approximate timings

0km Start: Welshpool, Powis Castle 10.15am

23.7km Sprint: Newtown 11.00am

67.8km Sprint: Llandrindod Wells 11.57am

100.3km KoM: Llyswen Hill [3] 12.38pm

126km KoM: Brecon Beacons [1] 1.12pm

153.9km Sprint: Mountain Ash 1.50pm

178.8km KoM: Caerphilly Mountain [1] 2.19pm

183.7km Finish: Caerphilly, Crescent Road 2.26pm