Cyclable gravel pass roads in the Alps
There are several worthwhile passes to visit in the Alps with a road bike where the road is not paved.
I only list passes that I have visited myself on this page.
Pass names in italics are difficult to cycle to and may require some walking.
Pass names in strike-through are strictly walking passes, but are included since I have been there.
Passes with an (*) are on the way to/from another pass (no.) in the section.
– If you cycle over the other pass you will have visited this too (without extra climbing).
(Scroll to the bottom for some further comments.)
Cycloclimbing.com

No. Name of passHeight (m)
1. flagflagCol Sommeiller Est 3000
2. flagflagCol Sommeiller *(1) 2993
3. flagPasso delle Platigliole 2908
4. flagflagViderjoch 2737
5. flagCol du Parpaillon (tunnel) 2637
6. flagflagGrand Col Ferret 2537
7. flagCol de la Cibičres 2525
8. flagColle di Lauson 2497
9. flagTridersattel/Alp Trida Sattel 2497
10. flagflagPass da Val Viola/Passo di Val Viola 2489
11. flagColle dell’Assietta *(8) 2472
12. flagCol du Vallon 2466
13. flagForcella Lavaredo/Paternsattel 2454
14. flagCol de Saluces *(12) 2444
15. flagColle Basset *(8) 2424
16. flagForcella Nuvolau/Rifugio Averau 2413
17. flagLüsner Scharte/Forcella Luson 2383
18. flagCol de la Traversette 2383
19. flagColle Blegier *(8) 2381
20. flagCol de la Valbelle 2372
21. flagColle Costa Piana (Cotte Plaine) *(8) 2313
22. flagBassa dell’Ajet 2310
23. flagCol des Embrasures *(18) 2305
24. flagColle Bourget *(8) 2299
25. flagPasso di Val Alpisella 2285
26. flagCol de Chérine 2270
27. flagflagPfitscher Joch/Passo di Vizze 2251
28. flagForcella di Pradazzo 2220
29. flagPasso della Costazza/Baita Segantini 2175
30. flag(Col de la) Croix de Coeur 2173
31. flagflagSandjöchl/Passo del Santicolo 2165
32. flagGiogo della Bala 2162
33. flagPass Tiarms 2150
34. flagDurannapass 2121
35. flagflagTilliacher Joch/Forcella Dignŕs 2094
36. flagPasso di Lusia 2056
37. flagflagKlanska Skrbina/Forcella della Lavina/Lahnscharte 2055
38. flagPasso di Fraele 1952
39. flagPasso Torre di Fračle *(38) 1941
40. flagflagCol de Tende/Colle di Tenda 1871

I sometimes use the (slightly modified) notation method for unpaved roads and paths from Centcols.org and their Chauvot guide: R1 is cyclable unpaved road. R1-2 is cyclable with difficulty on a race bicycle (mountainbike is recommended). R2 is where you will have to walk (with a road bike in any case). R3 is difficult to walk. S1 is a cyclable path (few such exists for race bikes). S2 is walking path. S3 difficult walking. S4 means carrying.
I give reference numbers to the Chauvot guide and to other guides from Centcols.org.