Six of the best climbs tracked by Velon in 2017

Nairo Quintana (Movistar Team), Tom Dumoulin (Team Sunweb) and Steven Kruijswijk (Team LottoNL-Jumbo) all feature as we select six of the best climbs tracked by Velon data in 2017 - from Blockhaus at the Giro d'Italia to Civiglio at Il Lombardia.

Giro Stage 9: Nairo Quintana on Blockhaus

A serious crash at the foot of the keenly-anticipated Blockhaus climb on Giro d'Italia Stage 9 puts Wilco Kelderman (Team Sunweb) out of the race. Geraint Thomas (Team Sky) also crashes but fights back with a brilliant climb to limit his losses.

Up at the front, Nairo Quintana (Movistar Team) mounts a sustained attack with five kilometres of the 13.6km category-one ascent remaining. (While the official distance of the climb is 13.6km, the road actually kicks up as much as 13km before that.)

Quintana's peak one-minute power of 430W distances the front group of favourites, some of the finest climbers in the world, on the steepest section of Blockhaus. 

Neither Vincenzo Nibali (Team Bahrain Merida) nor Thibaut Pinot (FDJ) can match his impressive acceleration and the Colombian takes the maglia rosa.

Quintana's decisive attack: 5km to go
- Time: 6'40"
- Speed: 17.3km/h
- Power: 368W
- 1min peak power: 430W

Giro Stage 9: Tom Dumoulin chasing Quintana

The race for the maglia rosa would be closely-fought over the three weeks, and although Dutchman Tom Dumoulin (Team Sunweb) does not match Quintana's stage-winning effort, he keeps in touch with his own impressive climb. At 561W Dumoulin's peak one-minute power is considerably higher than Quintana's, reflecting his higher weight.

Perhaps caught off guard by Quintana's initial attack, Dumoulin picks up the pace and catches Nibali and Pinot, with Bauke Mollema (Trek Segafredo) on his wheel.

Pinot (FDJ) and Dumoulin finish second and third respectively, 24 seconds down on Quintana. A manageable time gap for the Dutchman given his time-trial superiority. Read the full Stage 9 data summary

Dumoulin gives chase on Blockhaus
- Time: 6'34"
- Speed: 17.6km/h
- Power: 441W
- 60" peak power: 561W

Giro Stage 18: Steven Kruijswijk's late attack

Another punishing day on Giro Stage 18 - a relatively short but ridiculously difficult route, with five categorised climbs packed into 137km. Steven Kruijswijk (LottoNL-Jumbo), who came so close to winning the 2016 Giro, produces a fearsomely strong ride.

Sitting 10th in GC, he stays with the favourites through a mountainous stage, and impressively has enough left in his tank to attack at the end on the Pontives climb, gaining precious seconds in the overall classification and moving up to eighth.

After matching Dumoulin's earlier acceleration on Passo Gardena, the Dutchman pulls away from the GC leaders with Mollema and the pair grab 32 seconds.

Following attacks on Passo Gardena
- Time: 5'35"
- Speed: 23.7km/h
- Power: 385W
- 60" peak power: 434W – very high pace towards the top of Passo Gardena. Kruijswijk stays with the pink jersey and can follow his acceleration back to Quintana and Nibali.  

Attack in final 2.6km
- Time: 4'41"
- Speed: 33.3km/h
- Power: 364W
- 60’’ peak power: 416W 

Giro Stage 20: Nibali and Quintana strike back

The battle for the maglia rosa rumbles on: Nibali and Quintana are flying on the final climb of the race, taking 20 seconds from Dumoulin on Stage 20's final climb, before the descent to Asiago. 

The Italian is the lighter rider and that he shows higher power does not necessarily mean higher speed uphill. Nibali's one-minute peak power of 419W to Dumoulin's 436W wins precious GC seconds. 

Pinot, of FDJ, eventually sprints to a thrilling win from a group of favourites with Ilnur Zakarin (Team Katusha Alpecin) second and Nibali third.

Sitting fourth in GC, 53" down on race leader Quintana, Dumoulin is waiting for Stage 21 and the individual time trial ...

Final climb: last 2.5km
- Time: 6'24"
- Speed: 23.4km/h
- Power: 396W
- 60’’ peak power: 419W

Nairo Quintana: Giro Stage 20 
Final climb last 2.5km
Time: 6'24
Speed: 23.4km/h 
Power: 370W
60’’ peak power: 393W

Tom Dumoulin – 10th on stage - final climb
Final climb last 2.5km
Time: 6'35"
Speed: 22.8km/h 
Power: 422W
60" peak power: 436W

Tour de Suisse Stage 6: Consistent Caruso

As riders fine-tune their form for the Tour de France, or fight to make the final selection for July, it is impossible to find a harder one-week race than the Tour de Suisse.

Damiano Caruso (BMC Racing Team) averages a considerable 281W across Stage 6 from Locarno to La Punt, with a one-minute peak of 430W coming on the Albulapass climb.

It's not a stage-winning effort as Caruso finishes seventh, as Domenico Pozzovivo (AG2R-La Mondiale) solos to the win, but demonstrates how hard it is to compete at peak-season races like Tour de Suisse. See the full Tour de Suisse Stage 6 data summary

GC fight on Albulapass (6 to 3km on the climb)
- Time: 8'35"
- Speed: 21.2km/h.
- Power: 369W
- 1min peak power: 430W
- 2min peak power: 414W

Il Lombardia: Nibali seals second title

The final climb of the final Monument Classic of the season is where Nibali makes his decisive move in a hugely accomplished overall performance. He knows the climb and its gradients so well - which gives him an edge ahead of the final descent.

Nibali's descending skills means he will be impossible to catch after leading over the top of the Civiglio. He puts out an average of 462W in the decisive attack, which lasts for 1'31", and leaves Julian Alaphilippe (Quick-Step Floors) in his wake. See the full data summary for Nibali's victory

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