0km - No change in the overall standings as all the race favourites cross the line safely inside the peloton.
0km - Flecha takes second and Meyer third, before the other breakaway riders. And John Degenkolb leads the peloton over the line 40 seconds in arrears.
0km - Victory for Britain's Steve Cummings! What an amazing finale for the BMC man.
1km - Cummings leads inside the last kilometre. He looks back but it looks like it is his. Flecha and Meyer do not have enough in the tank...
2km - Cummings is trying to bury himself. He can't look back because he'll see the others right in his wheel. Saxo Bank are driving the peloton, but it's too late for them.
3km - Steve Cummings is time trialling his way to the finish. He has 20m over Flecha and Meyer. A trio is another 30m back.
3.5km - De Gendt is back with the leaders, but Cummings launches a big attack. Meyer is the first to respond, with Flecha.
4km - The Orica-GreenEdge pair of Meyer and Clarke rejoin the leaders, along with Gerdemann. De Gendt is still a bit further back. That trio has been caught by the peloton, but the gap to the peloton is still 49 seconds.
5km - It's Cummings who shuts down the gap to Flecha, joining the Spaniard off the front.
6km - Juan Antonio Flecha launches an attack off the front! There's indecision as to who will chase down, but Meyer, Clarke and Gerdermann just look at each other.
7km - The leaders pass under the 7km-to-go banner. They may hold on, given the turmoil behind. The Moreno trio pass through at 31 seconds and the pack at 40 seconds, with Rabobank now on the front.
8km - It's Dani Moreno, Gert Steegmans and Andrey Kashechkin riding in the trio ahead of the pack - this is interesting. Moreno is a threat on GC.
10km - The green jersey Degenkolb has responded to all the attacks but on his own, without any team-mates. But the latest trio of riders manage to open up a small gap off the front... The trio trail the seven leaders by 32 seconds, with the peloton another 4 seconds back.
11km - Now Paolo Tiralongo ups the pace for Astana on the front of the peloton. Degenkolb is completely isolated so this is proving to be an intriguing finale. The seven-man group have 25 seconds but it looks like Tiralongo is trying to form a counter attacking group to hunt them down, given the peloton's inability as a whole to cut the gap itself.
12km - Saxo Bank and Katusha are near the front of the peloton - but they're not there to lead the chase, just to keep their men out of trouble. The only riders trying to pull it back are Argos, down to two, and Lotto, who are half ill. It's down to 40 seconds though over these undulating rural roads.
13km - This is really fascinating: the stength of the break is such that the peloton cannot make any in-roads. The gap is 59 seconds still. Mikel Astarloza of Euskaltel picks up a rear puncture and needs a wheel change off the back of the pack.
15km - Argos Shimano have disappeared from the front of the bunch: there is just one rider from the Dutch team, plus the green jersey Degenkolb. In fact, as a result of the fall in pace, the gap has got bigger: one minute again, with 15km to go.
17km - There are no classified hills today but there are numerous hills nonetheless - and the leaders are on one of those right now. It's a narrow road and the wind seems to be now blustering quite hard - you can see it in the trees, bushes and vegetation that lines the road. The gap is 50 seconds.
18km - Some of the riders who have been dropped from the peloton include Juan Jose Cobo, Dani Moreno, Assan Bazayev...
21km - The lead is down to 58 seconds but the riders on the front of the peloton look very tired. The next three days in the mountains will be brutal - surely many more riders will be dropping out of the race. Riders continue to lose contact in twos and threes off the back. There will be some big gaps tonight.
23km - The fast pace in the pack has seen some riders fall off the back. In fact, the whole race has blown apart with the bunch stretched out adn numerous riders completely losing touch, including Jurgen van den Broeck, who has had a very disappointing race.
25km - The route runs right down by the water and then crosses a bay on a narrow man-made peninsula and then bridge. Winds could create problems here, but they don't appear to be so strong. The gap is 1:25.
28km - The peloton is really strung out as they approach Ferriol on a wide motorway. The seven leaders have 1:42 at the moment. Apparently, half the Lotto Belisol team has been hit by a virus - although Gianni Meersman is one of those unaffected. He'll fancy his chances today for a high finish - although it would take a miracle to beat Degenkolb and his well-oiled Argos train.
32km - The break is not coming down as quick as Argos would like - it has stayed around the two-minute mark for quite some time.
35km - The lead dips below the two-minute mark, before returning to around 2:05. Cheng Li, the first Chinese rider in the Vuelta, is on the front of the peloton for Argos Shimano. Lotto Belisol are helping out too.
40km - Steve Cummings, the only British rider in the Tour de France not to win a stage, drops back to talk to his BMC team car and pick up some liquids. The leaders have 2:15 still over the pack as they pass a sign that marks 18km to Ferriol: the route takes the riders through the finish town and then on a loop round and back to Ferriol. They like these conclusing loops in the Vuelta - gives the fans two opportunities to go wild.
45km - The seven leaders - Juan Antonio Flecha (Sky), Linus Gerdemann (RadioShack), Simon Clarke, Cameron Meyer (both GreenEdge), Thomas de Gendt (Vacansoleil), Stephen Cummings (BMC) and Elia Viviani (Liquigas) - have 2:20 over the pack, which is being driven by Argos Shimano. Numerous riders from Movistar, Sky and GreenEdge lurk in the wings, while the Katusha team of red jersey Joaquim Rodriguez are having a welcome day off.
50km - The withdrawal of Bouhanni makes Dekenkolb's win today look even more likely. The Frenchman was getting closest to the German in the sprints, while Viviani will be tired out after contributing to the break. Ben Swift clearly has not got the acceleration, while Bennati doesn't have the power.
53km - Argos Shimano are driving a fast pace on the front of the peloton, reducing the gap to 2:12. The TV motorbike is pretty close to the front of the pack and prompts a wave of the arm from one GreenEdge rider, who clearly doesn't want Argos taking any slipstream assistance from the bike, what with two men - Meyer and Clarke - up in the break.
55km - Big news: Nacer Bouhanni, the French national champion, has pulled out of the race. The FDJ-BigMat sprinter was involved in that crash yesterday and is clearly suffering today.
60km - It looks like Cam Meyer is going to be part of a third doomed breakaway: the gap is down to 2:27 now. Simon Clarke of Orica-GreenEdge appears to be having a problem with his bike and is off the back as he fiddles around with his gearing. Now his team car draws up alongside and he has a chat.
65km - The lead drops to below three minutes - normally it's the opposite after the feeding zone, where the peloton habitually takes its foot off the gas. It means Argos and Lotto mean business today. They want a bunch sprint in Ferriol.
70km - Spaniard Jose Joaquin Rojas (Movistar) needs to see the race doctor while escapee Thomas de Gendt drops back to his Vacansoleil team car for some mechanical assistance. The leaders are passing through the feeding zone and the gap is 3:12.
72km - The favourite for the win is John Degenkolb, who could make it five today in Ferrol. "My goal today is to move back to the top of the green jersey standings," he said this morning. "I will do my best. People are talking about me winning a fifth stage like Mark Cavendish once did in the Tour de France, but I'm not thinking about that too much." The German is third in the points standings, behind Rodriguez and Valverde.
75km - The gap is 3:12 for the seven leaders. Yesterday's crash that forced the withdrawal of Xabier Zandio and Morris Possoni also brought down French national champion Nacer Bouhanni. "I fell with Zandio and Possoni but I wasn't riding that quickly. My knee hit my handle bar and that hurt a bit but I hope everything will be okay today. I know that if I feel strong my team-mates will help me as much as they can," the FDJ rider said.
80km - The break passes through the crowded town of A Coruna for the first intermediate sprint, which de Gendt takes ahead of Viviani and Gerdemann. No changes at the top of the points classification.
83km - The lead is down to three minutes for the seven escapees. The average speed for the second hour of the stage was 43.6km/h.
88km - The final rider in this group, Elia Viviani, is an Italian track specialist still looking for a maiden stage win on a Grand Tour. A multiple national and European track champion, 23-year-old Viviani has spent his entire career at Liquigas since turning professional in 2010. Should this break come down to a sprint finish, Viviani would be the dangerman alongside Clarke.
90km - The gap is very stable at the moment: 3:40 despite the effort by Argos Shimano and Lotto Belisol to reduce the deficit. Back to our round-up: German Linus Gerdemann is a powerful rouleur who has won both the Tour of Germany and Tour of Luxembourg in the past. The 29-year-old wore the yellow jersey for one day in his debut Tour de France in 2007 after winning stage seven.
95km - Briton Steve Cummings is riding his debut Vuelta and is a former track specialist with an Olympic silver medal to his name from Athens 2004. After a couple of years at Sky, the 31-year-old joined BMC in 2012 and rode the Tour de France in support of Cadel Evans. In a Tour dominated by British riders, Cummings was the only Brit not to win a stage on the race (Wiggins, Cavendish, Froome and Millar all emerged victorious on at least one occasion).
100km - Vacansoleil-DCM's Thomas de Gendt, 25, finished 3rd in the Giro d'Italia after a sensational solo win atop the Stelvio climb. The Belgian missed the Tour because he was getting married - and after a poor start to the Vuelta, he was involved in a break in the opening week. Next season he'll be joined at Vacansoleil by Juan Antonio Flecha. The veteran Spaniard from Team Sky is a classics specialist and has won a stage of the Tour in 2003.
102km - There's quite a strong headwind at the moment for the leading seven riders. Let's take a closer look at them. Orica-GreenEdge have two in the break: Simon Clarke, 26, outsprinted Tony Martin to win stage four in the ski resort of Valdezcarey; Cameron Meyer, 24, is a previous winner of the Tour Down Under. He finished 8th in Wednesday's time trial and was involved in the break in stage eight and in yesterday's stage 12.
105km - There's a big track cycling pedigree in this group: Meyer, Clarke, Cummings and Viviani all made their names in track cycling before making the transition across to the road. Viviani is still fairly active on the track - he took sixth place in the omnium event at London 2012. The gap is up to 3:37.
108km - The leaders have completed a long downhill drag and edge towards the town of Carballo with a lead of 3:10 over the pack. So, the gap is not being allowed to get too big, that's for sure.
110km - Argos Shimano are getting some help from Lotto Belisol on the front of the pack. The Belgian team also missed out on this break - and they have sprinters Gianni Meersman and Vincente Reynes to consider.
115km - It's quite a break: Flecha is a specialist at this kind of thing, Clarke has already won a stage in this year's race from a break, Meyer has been involved in two breaks, Gerdemann is a strong rouleur, Viviani is a fast sprinter and would be the man to watch (along with Clarke) if this break stays out, de Gendt is a powerful all-round rider who needs no introductions and Cummings is a team-man who now has a chance of personal glory.
118km - Right on cue, Argos Shimano come to the front of the pack to control the race. They will not want the break to get too far ahead. The gap is currently just under three minutes.
120km - This is a fascinating scenario: Katusha have no need to chase; Sky have effectively admitted that Ben Swift cannot win a bunch finish, as have Liquigas with Elia Viviani placed in the group. So it will all come down to Argos Shimano and, perhaps, FDJ-BigMat (for their man Nacer Bouhanni) to lead the chase. Degenkolb may already have four wins, but he wants a fifth...
122km - The best-placed rider of the escapees is Linus Gerdemann, who is currently 43:48 down on Joaquim Rodriguez on GC. As such, expect no effort from Katusha in leading the chase - their man is safely in red ahead of the three successive mountain stages coming up. The lead is now 2:23 for the escapees.
125km - This finally looks to be the decisive break: the lead is up to 1:22 and the seven riders are combining well. But with sprinter Elia Viviani there, the Argos Shimano team of John Degenkolb won't let the lead get too big, surely.
128km - The seven leaders now have 30 seconds over the peloton. The average speed for the first hour of racing today was 45.4km/h.
130km - Another break has formed, this time with seven riders: Juan Antonio Flecha (Sky), Linus Gerdemann (RadioShack), Simon Clarke, Cameron Meyer (both GreenEdge), Thomas de Gendt (Vacansoleil), Stephen Cummings (BMC) and Elia Viviani (Liquigas).
132km - It's all over for that large break: they are reeled in and the peloton is back as one.
135km - Movistar and Saxo Bank are leading the chase on the front of the peloton and the 24 leaders are making little headway.
137km - This large break features Ian Stannard, Danny Pate, Daniele Bennati, Cameron Meyer, Jose Joaquin Rojas, Dario Cataldo, Martijn Maaskant, Ruben Perez, Angel Vicioso, Pablo Lastras, birthday boy Matti Breschel, Klaas Lodewych, Mauro Santambrogio, Biel Kadri, Romain Sicard, Christophe Le Mevel, Gregory Rast, Danail Andonov, Alexsandr Dyachenko, Kevin Seeldrayers, Rob Ruijgh, Allan Davis and Nico Sijmens.
138km - We now have a huge group of 24 riders off the front of the peloton - and this stands a greater chance of staying out, given its size. Names coming right up.
140km - Red jersey Joaquim Rodriguez moved back into the top of the points classification with his second stage win yesterday. Rodriguez has 119 points and Alejandro Valverde is now second with 106 points, three ahead of four-time stage winner John Degenkolb. But Valverde is the current king of the mountains so today wears the blue polka dot jersey again, meaning the green jersey wearer is still Degenkolb, despite being third in the standings.
143km - Three more riders joined the Cobo break but it has now been swept up by the pack. Intriguing stuff so far today.
145km - Remember Juan Jose Cobo, the man who won last year's Vuelta? Well, the Spanish forgotten man - now at Movistar - is riding in a break of a dozen riders off the front of the peloton.
148km - Bazayev has been swept up by the peloton, leaving Duque to ride solo off the front. Unsurprisingly, the Colombian is also caught by the pack. The temperature is up to 21 degrees.
150km - Kazakh pocket rocket Assan Bazayev (Astana) and Colombian veteran Leonardo Duque (Cofidis) have 10 seconds over the pack.
152km - This is yet another fast and frenetic opening to the stage - much like yesterday, where it took 75km for the main break to stick. Another rider joined the leaders but they have been reeled in now, sparking a counter attack from another cluster of riders.
155km - Eight more riders have joined the two escapees. Spanish Pro Conti teams Andalucia and Caja Rural have missed out and are fighting on the front of the peloton to pull back the break. Aramendia is back with the bunch after being distanced early on.
158km - Another withdrawal to report: RadioShack-Nissan's Hayden Roulston signed on this morning but didn't take to the start, so we're down to 189 riders.
160km - The two leaders have just 20 seconds over the peloton as Euskaltel, Lotto Belisol and Vacansoleil combine on the front in a bid to reel them in.
165km - Jan Bakelants (RadioShack-Nissan) and Johan van Summeren (Garmin-Sharp) break clear of the peloton. Meanwhile, off the back of the pack is Javier Aramendia of Caja Rural, the most aggressive rider of this year's Vuelta so far.
170km - The teams of Caja Rural and Vacansoleil-DCM - both without a win so far - are very active on the front. It's been a very fast start to this undulating stage that should favour a breakaway.
173km - They're off! American Andrew Talansky (Garmin-Sharp) picks up a puncture 500m from the start and needs a wheel change. It is currently 19 degrees Celsius in Santiago de Compostela - famous for the Catholic pilgrimmage route, the Way of St James.
12:30 - The riders are rolling through the neutral zone ahead of the official start of today's stage. Yesterday, Team Sky's Xabier Zandio was forced to retire from the race with a head injury following a big crash 33km from the finish. Lampre's Morris Possoni completed the stage with a nasal laceration but was forced to retire from the race after needing 15 stitches to his wound. We are down to 190 riders for the start of stage 13.
12:25 - British hope Chris Froome (Team Sky) struggled on the demanding Cat.3 climb - which featured debilitating ramps of 20 per cent - and finished in fifth place, 23 seconds behind Rodriguez. Froome stays in third place on GC but now trails the red jersey by 51 seconds. A late rally by Spain's Alejandro Valverde saw the Movistar rider take third place on the stage, 13 seconds in arrears. Valverde retains his fourth place on GC but drops to 1:20 behind his compatriot Rodriguez. General classification
12:20 - Yesterday, Spain's Joaquim Rodriguez won a punchy uphill finish at Mirador de Ezaro to take his second stage win of the Vuelta and extend his race lead. In a trademark display of explosive uphill sprinting, Katusha captain Rodriguez dropped his principal rival Alberto Contador in the final 100m of the last climb to cross the line eight seconds clear of the Saxo Bank-Tinkoff rider - and extend his overall buffer to 13 seconds on the GC. Report: Rodriguez extends lead with second stage win
12:15 - Welcome to live coverage of stage 13 of the Vuelta a Espana - a rolling 173km ride from Santiago de Compostela to the industrial port of Ferrol. This could offer the sprinters one final chance to shine ahead of a series of gruelling mountain-top finishes.