EXTREMEIT · Lombardia · SS42 dir/A

Passo del Mortirolo

Eleven kilometres of the hardest climb in Italian cycling, called corner by corner.

Mazzo di Valtellina to the Passo del Mortirolo, the hard side.

Corners coloured by severity · tightest in red

11.3km
LENGTH: 117
CORNERS CALLED: 9
HAIRPINS: 10.3
CORNERS / KM: +1284m
CLIMB: 1845m
HIGH POINT: 11.3%
AVERAGE GRADIENT

The Mortirolo is short and it is savage. From Mazzo di Valtellina the road climbs to 1,852 metres in a little over eleven kilometres, averaging more than eleven per cent the whole way. That is why it became the mountain the Giro d'Italia uses to break a race, and the climb Marco Pantani made his own in 1994.

It does not look like a famous road. Most of it is tagged as an unclassified road in OpenStreetMap: single track, no lane markings, no lighting, walled in by trees. Every corner below is generated from that road's real geometry, and the app speaks them in the same notation.

Only nine of the 117 calls are hairpins, which is what makes the Mortirolo unlike the passes it is usually listed beside. This is not a switchback staircase. It is a narrow road that simply never straightens, at over ten calls per kilometre.

The grade histogram tells the same story from the other side: this is a road of 3s and 4s arriving continuously, with almost no open running in between. On a climb this steep and this blind, knowing what the next corner does matters more than on a road twice its length.

THE STAGE MAP

Every corner, where it actually is.

startH · hairpinSQ · square123456

THE CLIMB

Elevation profile.

557 m → 1845 m over 11.3 kmvertical scale ×2.1elevation from a terrain model, not a survey

CORNER MIX

What the road is actually made of.

9hairpin
2square
291
102
173
254
215
46

THE PACENOTES

All 117 calls, in order.

Every call Tornante makes on Passo del Mortirolo, in order. Distances are from the stage start to the corner’s turn-in.
At	Call	Notes	Radius	Turn	Altitude
0000m	R1		17 m	93°	557 m
0175m	L2		23 m	90°	561 m
0260m	L5-		81 m	17°	565 m
0305m	R square		15 m	96°	567 m
0385m	L1+		20 m	72°	573 m
0435m	R1		13 m	24°	579 m
0465m	L1		18 m	27°	581 m
0525m	L3+		41 m	56°	588 m
0585m	R1	long	10 m	140°	596 m
0655m	L3		31 m	32°	609 m
0710m	R3		39 m	35°	616 m
0755m	L1	long	9 m	157°	623 m
0840m	R4		66 m	13°	632 m
0905m	R4		62 m	25°	643 m
0965m	L3		37 m	66°	652 m
1035m	R4		49 m	45°	660 m
1100m	R4		57 m	26°	665 m
1275m	R4		70 m	21°	699 m
1340m	L4		72 m	21°	712 m
1405m	R2	long	24 m	153°	727 m
1640m	L hairpin		8 m	162°	781 m
1855m	R hairpin		9 m	161°	795 m
2095m	L2		24 m	51°	812 m
2175m	R2		27 m	41°	819 m
2255m	L1		18 m	48°	828 m
2310m	L1	long	18 m	125°	833 m
2420m	L5		85 m	15°	844 m
2470m	R5-		79 m	48°	847 m
2670m	R5		104 m	20°	867 m
2730m	L4		59 m	30°	875 m
2835m	R3		35 m	43°	887 m
2905m	L3		39 m	29°	893 m
2955m	R square		11 m	94°	901 m
3005m	R1		12 m	74°	908 m
3060m	L4+		77 m	16°	919 m
3195m	L5		113 m	14°	939 m
3315m	R4		68 m	15°	953 m
3365m	L4		64 m	38°	960 m
3455m	R5-		80 m	32°	979 m
3560m	L hairpin		13 m	174°	1000 m
3655m	R5		86 m	13°	1016 m
3765m	R1	long	11 m	156°	1026 m
3925m	L hairpin		10 m	168°	1058 m
4040m	R5		92 m	47°	1079 m
4150m	R5		87 m	21°	1085 m
4215m	L3+		40 m	24°	1090 m
4260m	R3		36 m	59°	1094 m
4360m	L5-		79 m	20°	1110 m
4450m	R1	long	12 m	139°	1123 m
4530m	R3		31 m	20°	1134 m
4575m	L2		23 m	34°	1140 m
4620m	L1		16 m	60°	1145 m
4680m	R4		60 m	36°	1153 m
4805m	L1	long	10 m	153°	1175 m
4900m	R1	long	10 m	151°	1189 m
5040m	R5		132 m	18°	1206 m
5255m	R3		35 m	32°	1220 m
5310m	L2		28 m	27°	1224 m
5350m	L1	long	8 m	154°	1228 m
5420m	R1	long	8 m	142°	1236 m
5485m	L6-		154 m	12°	1242 m
5540m	L1	long	9 m	145°	1249 m
5640m	R5		134 m	18°	1265 m
5715m	L5		106 m	22°	1274 m
5775m	R1	long	7 m	156°	1279 m
6000m	R5		91 m	19°	1317 m
6145m	L hairpin		11 m	174°	1329 m
6240m	R3		39 m	22°	1343 m
6370m	L5		115 m	23°	1364 m
6590m	R6		166 m	17°	1388 m
6720m	R5		135 m	25°	1398 m
6815m	R1	long	8 m	132°	1408 m
6895m	L1		16 m	68°	1422 m
6955m	R2		23 m	88°	1431 m
7035m	L1	long	9 m	135°	1440 m
7095m	R1		8 m	118°	1443 m
7140m	L hairpin		8 m	161°	1447 m
7225m	L4		53 m	32°	1459 m
7310m	R6-		159 m	19°	1470 m
7620m	R1	long	8 m	157°	1503 m
7690m	L3		36 m	27°	1509 m
7735m	R4		67 m	14°	1517 m
7845m	R4		62 m	23°	1530 m
7895m	L hairpin		10 m	162°	1537 m
8055m	L3		33 m	21°	1552 m
8170m	R1	long	8 m	156°	1564 m
8295m	R4		61 m	25°	1577 m
8355m	L4-		42 m	22°	1579 m
8405m	R4		52 m	42°	1580 m
8645m	L5		124 m	24°	1600 m
8765m	L5-		79 m	14°	1612 m
8805m	R2		21 m	59°	1616 m
8870m	L4		48 m	40°	1622 m
8950m	L3		34 m	49°	1630 m
9025m	R2		25 m	55°	1641 m
9120m	L3		31 m	37°	1655 m
9190m	R4		67 m	24°	1661 m
9315m	L5		87 m	33°	1674 m
9525m	R4-		44 m	39°	1690 m
9680m	L2		24 m	48°	1704 m
9745m	R3		34 m	58°	1711 m
9820m	L hairpin		9 m	166°	1719 m
9985m	R1	long	14 m	123°	1738 m
10090m	L1	long	14 m	138°	1753 m
10190m	R5		92 m	18°	1764 m
10275m	R3		32 m	100°	1770 m
10365m	L4		46 m	34°	1773 m
10410m	L5		87 m	18°	1775 m
10450m	L4		69 m	45°	1778 m
10555m	R1	long	8 m	122°	1785 m
10620m	L1	long	8 m	140°	1790 m
10715m	R hairpin		13 m	167°	1799 m
10875m	L4-		42 m	23°	1808 m
10950m	L1	long	10 m	152°	1812 m
11035m	R4		62 m	26°	1824 m
11165m	L4		48 m	24°	1837 m
11240m	R6-		160 m	13°	1843 m

How to read these notes

A call is a direction and a grade: L or R, then 1 (tightest) to 6 (barely a bend). A + or − means the corner sits near the edge of its band. Corners too tight for the ladder are named instead: hairpin, open hairpin, square.

The Notes column carries the modifiers a co-driver would add: tightens, opens, long, don’t cut. Radius is the tightest sustained apex radius the engine measured, and Turn is the total heading change through the corner. Those are the two numbers behind the grade.

HOW IT SOUNDS

The opening of the stage, as spoken.

0m“20, right 1”
175m“80, left 2 and left 5”
305m“20, square right and left 1”
435m“20, right 1 and left 1”
525m“40, left 3 into right 1 long”
655m“20, left 3 and right 3”

QUESTIONS

Passo del Mortirolo, in brief.

How steep is the Mortirolo?

This stage gains about 1,285 m over 11.3 km, an average of roughly 11%, which is exceptional for a climb of that length. We do not publish a maximum-gradient figure, because the open terrain model available for this road cannot resolve individual ramps well enough for that number to be meaningful.

Which side of the Mortirolo is the hard one?

The Mazzo di Valtellina side, which is the one on this page. The approaches from Monno and Grosio are both longer and gentler.

Is the Mortirolo open in winter?

No. OpenStreetMap records the pass road as closed from November to April. Check locally before you go, because these dates move with the snow.

WHERE THIS COMES FROM

Measured, not written.

Every corner on this page was generated by the same engine that runs in the app, from the road’s own geometry: Strada del Mortirolo (SS42 dir/A), mapped by OpenStreetMap contributors and tagged unclassified, asphalt. The engine is deterministic: the same road always produces the same notes, so this table is exactly what the app will say to you.

Elevation comes from an open terrain model rather than a survey, so altitudes are close but not exact. Corner grades are computed estimates, not measurements of how the road should be driven.

Drive it with the calls.

Passo del Mortirolo ships with the app. Start the stage and Tornante speaks each of these calls as you reach it, timed to your GPS, so your eyes stay on the road rather than on a screen.

Get Tornante

NEXT ROAD

Other called stages.

Corner density on this stage: 10.3 calls per kilometre.