Nausea Index: road trips
The bumpiest road trips, ranked
Some famous drives earn their reputation one hairpin at a time. This table ranks every route in our road trip guides by how likely it is to make a passenger carsick, and names the exact stretch where it usually starts.
This cut of the Dizzout Nausea Index ranks 46 road trips. 17 entries sit in the top band, rated notorious: Chiang Mai to Chiang Mai (loop), Coll dels Reis to Port de sa Calobra, Curtea de Arges to Cartisoara and 14 more. Every rating is the one already published in the entry's own Dizzout guide, so a row summarizes a full guide, not a lab test.
Sort by length or country to plan around it, and open any drive for its full guide: the risk sections, the best seat, and what helps mid drive.
| Rank | ||||||
|---|---|---|---|---|---|---|
| 1 | Chiang Mai to Chiang Mai (loop) | Thailand | mountain loop road | 373 | Notorious 92 | Route 1095 Chiang Mai to Pai (signed at 762 curves) |
| 1 | Coll dels Reis to Port de sa Calobra | Spain | cliffside hairpin descent | 7.6 | Notorious 92 | Nus de sa Corbata (270 degree loop) |
| 1 | Curtea de Arges to Cartisoara | Romania | alpine switchback pass | 70 | Notorious 92 | Balea waterfall to Balea Lake (13 km of switchbacks) |
| 1 | Denver to Aspen | United States | mountain highway | 200 | Notorious 92 | Eisenhower Tunnel approach |
| 1 | Inverness to Inverness (loop) | United Kingdom | single-track rural roads | 516 | Notorious 92 | Bealach na Bà (Applecross Pass) |
| 1 | Kahului to Hana | United States | jungle cliff road | 52 | Notorious 92 | Twin Falls to Wailua |
| 1 | Lauro Muller to Bom Jardim da Serra | Brazil | escarpment switchback climb | 21 | Notorious 92 | The 12 km escarpment wall |
| 1 | Nikko to Lake Chuzenji | Japan | one-way mountain hairpin roads | 9.8 | Notorious 92 | Second Irohazaka uphill hairpin stack |
| 1 | Prato allo Stelvio to Bormio | Italy | high alpine hairpin pass | 29 | Notorious 92 | The hairpin ladder above Prato allo Stelvio (48 bends on the South Tyrol ramp) |
| 1 | Rome to Amalfi | Italy | highway then coastal cliff | 175 | Notorious 92 | SS163 between Vietri and Amalfi |
| 1 | San Francisco to Los Angeles | United States | coastal cliff road | 460 | Notorious 92 | Big Sur (entire stretch) |
| 1 | Sorrento to Salerno | Italy | coastal cliff road | 35 | Notorious 92 | Positano to Praiano cliff stretch |
| 1 | Sospel to La Bollene-Vesubie | France | narrow rally mountain pass | 19 | Notorious 92 | Sospel to Moulinet hairpins |
| 1 | Tail of the Dragon (Deals Gap) to Tabcat Creek Bridge | United States | tight two-lane mountain road with near-continuous curves | 11 | Notorious 92 | The named curve clusters - Copperhead Corner, Hog Pen Bend, Gravity Cavity and Brake or Bust Bend |
| 1 | West Glacier to St. Mary | United States | mountain pass | 50 | Notorious 92 | The Loop switchback |
| 1 | Zhangjiajie to Tianmen Cave | China | stacked mountain switchbacks (bus only) | 6.7 | Notorious 92 | Lower switchback wall |
| 1 | Zurich to Zurich (loop) | Switzerland | alpine mountain roads | 1,000 | Notorious 92 | Fluela Pass (2,383 m) |
| 18 | Andalsnes to Valldal | Norway | mountain hairpin wall | 31 | Rough 75 | The 11 hairpin wall above Isterdalen |
| 18 | Baddeck to Baddeck (loop) | Canada | coastal mountain road | 185 | Rough 75 | MacKenzie Mountain switchbacks (descent to Pleasant Bay) |
| 18 | Bruck an der Grossglocknerstrasse to Heiligenblut | Austria | engineered alpine toll road | 30 | Rough 75 | Fuscher Torl climb from the Bruck side |
| 18 | Cherokee, NC to Waynesboro, VA | United States | mountain scenic highway | 469 | Rough 75 | Asheville to Boone (most curves) |
| 18 | Da Nang to Lang Co | Vietnam | coastal mountain pass | 13 | Rough 75 | South side switchbacks above Da Nang |
| 18 | Dubai to Fujairah | United Arab Emirates | mountain highway | 85 | Rough 75 | Wadi Ham mountain pass |
| 18 | Dubai to Muscat | United Arab Emirates / Oman | desert highway then mountain | 290 | Rough 75 | Wadi Jizzi mountain pass |
| 18 | Hout Bay to Noordhoek | South Africa | coastal cliff road | 5.6 | Rough 75 | Ascent out of Hout Bay to Chapman's Point |
| 18 | Los Andes to Mendoza | Chile / Argentina | high Andes switchback crossing | 165 | Rough 75 | Los Caracoles switchback wall (29 bends) |
| 18 | Manali to Leh | India | high altitude mountain highway | 265 | Rough 75 | Gata Loops (21 hairpin bends) |
| 18 | Marrakech to Ouarzazate | Morocco | mountain pass highway | 122 | Rough 75 | Taddert to the summit climb |
| 18 | Queenstown to Wanaka | New Zealand | high country hairpin road | 43 | Rough 75 | The zigzag above Arrow Junction |
| 18 | Te Anau to Milford Sound (Piopiotahi) | New Zealand | alpine valley road with a steep hairpin descent | 74 | Rough 75 | Homer Tunnel descent (1.2 km, ~1:10 grade, single-lane, unlined granite) |
| 18 | Torquay to Allansford | Australia | coastal cliff road | 150 | Rough 75 | Lorne to Apollo Bay |
| 18 | Underberg to Mokhotlong | South Africa / Lesotho | gravel 4x4 mountain pass | 58 | Rough 75 | Switchback stack below Sani Top |
| 33 | Bangkok to Chiang Mai | Thailand | mixed (highway then mountain) | 435 | Manageable 50 | Lampang to Chiang Mai mountain section |
| 33 | Cape Town to Port Elizabeth | South Africa | coastal highway | 470 | Manageable 50 | Sir Lowry's Pass |
| 33 | Chicago to Santa Monica | United States | mixed (urban, plains, desert, mountain) | 2,448 | Manageable 50 | Sandia Mountains (New Mexico) |
| 33 | Killarney to Killarney (loop) | Ireland | narrow coastal loop road | 111 | Manageable 50 | Coomakista Pass between Waterville and Caherdaniel |
| 33 | Los Angeles to Las Vegas | United States | desert highway | 270 | Manageable 50 | Cajon Pass |
| 33 | Miami to Key West | United States | overseas highway | 165 | Manageable 50 | Seven Mile Bridge |
| 33 | Reykjavik to Reykjavik (loop) | Iceland | two-lane rural road | 813 | Manageable 50 | East Fjords (entire stretch) |
| 40 | Dubai to Abu Dhabi | United Arab Emirates | desert highway | 95 | Gentle 25 | Interchange 8 traffic backups |
| 40 | London to Edinburgh | United Kingdom | motorway | 405 | Gentle 25 | M25 entry traffic |
| 40 | Nashville to Natchez | United States | scenic parkway | 444 | Gentle 25 | None significant |
| 40 | New York to Washington DC | United States | highway | 230 | Gentle 25 | New Jersey Turnpike near tunnels |
| 40 | Paris to Nice | France | autoroute | 580 | Gentle 25 | A7 Vallée du Rhône heavy summer traffic |
| 40 | Sydney to Melbourne | Australia | highway | 545 | Gentle 25 | Goulburn descent |
| 40 | Tokyo to Kyoto | Japan | high-speed rail | 320 | Gentle 25 | None - entire route is smooth |
46 entries. Equal ratings tie on purpose: the guides rate in four bands, and this table does not pretend to more precision than they carry.
How this table is ranked
Each drive inherits the rating already published in its Dizzout route guide. A guide rates a route in one of four bands, gentle to notorious, from the road's own geometry (switchback density, grades, how long the winding sections run), its terrain, and what passengers consistently report. The bands map to fixed scores (gentle 25, manageable 50, rough 75, notorious 92), and equal ratings tie.
This is a motion sickness ranking, not a safety ranking. A road can be superbly engineered and still fold a back seat passenger in ten minutes, and the worst stretch column names where that tends to happen.
The data behind this table
- The full Nausea Index: every rated journey on the site in one cross category list.
- The World Nausea Map: the same ratings placed where they actually are.
- Motion sickness statistics: who gets motion sick, and how often, with sources.
Riding one of these roads soon?
Stop car sickness
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Questions people ask
What is the bumpiest road trip for motion sickness?
Our guides rate 17 entries notorious, the top band: Chiang Mai to Chiang Mai (loop) (Route 1095 Chiang Mai to Pai (signed at 762 curves)); Coll dels Reis to Port de sa Calobra (Nus de sa Corbata (270 degree loop)); Curtea de Arges to Cartisoara (Balea waterfall to Balea Lake (13 km of switchbacks)); and 14 more. Equal ratings tie on purpose, and each name links to the full guide behind its rating.
What pushes a drive into the top band?
Continuous switchbacks with no straight recovery sections, long steep descents, and curves that arrive faster than a passenger can anticipate them. The Sa Calobra road packs about 26 bends, most of them hairpins, into under 8 miles, the Stelvio carries 48 bends on its South Tyrol ramp alone, and the Road to Hana runs 620 curves in 52 miles. Length matters less than density: a short pass can outrank a full day drive.
Is a very high rating a reason to skip the drive?
Usually not. These are some of the best drives in the world, which is exactly why they are in our guides. The rating tells you to prepare: put the queasiest passenger in the front, plan stops at the viewpoints, keep eyes off screens through the worst stretch, and have relief ready before the bends start.
Keep going
- Every route guide, road by road
- Road trip nausea: the full prevention guide
- Turn a trip date into a day by day prep checklist
Other cuts of the index: roughest sea crossings, biggest cruise ships, worst disney and universal rides.
Updated 2026-09-05. Ratings and figures come from the Dizzout guides linked in each row and change only when a guide changes. This page is educational and is not medical advice.