| Status | Road | Name | District | Length | Lighting | Alternative Route |
 | 616 | Oldeidstunnelen | Sogn og Fjordane | @200m | Yes | |
 | 562 | Olsvik | Hordaland | 1074m | ? | Go around the tunnel. |
| 15 | Oppljos | Sogn og Fjordane | 3550m | ? | Go via the Rv 258 -old Strynfjellet road (summer only). |
| 23 | Oslofjordtunnelen | Akershus | 3988m | ? | The tunnel's total length is 7300m, there is no alternative route. |
| 23 | Oslofjordtunnelen | Buskerud | 3318m | ? | Tunnel total length is 7300m, there is no alternative route. |
| 15 | Ospeli | Sogn og Fjordane | 2549m | ? | Go via the Rv 258 -old Strynfjellet road (summer only). |
 | 62 | Øksendalstunnelen | Møre og Romsdal | 6000m | Yes | There is a road around it that follows the edge of the fjord to the north but it will add a few km to your journey and involves a bit of climbing. |
| 714 | Perviktunnelen | Sør Trøndelag | 630m | ? | Take the boat or bus. |
| 868 | Pollfjellet | Troms | 3230m | ? | This tunnel is closed to bicycles but has a handy bikepath around it. (summer only). |
| 356 | Porsgrunn | Telemark | 860m | ? | Go via the local road. |
| 5 | Purkehola | Sogn og Fjordane | @330m | ? | |
| 564 | Ranten | Hordaland | 74m | ? | Go around the tunnel. |
| Unclassified | Raudbergtunnelen | Hordaland | 530 m | Yes | None. Walking over the mountain (400 m) carrying your bike is NOT RECOMMENDED as the terrain is very steep with cliffs and thickly forested, and the path is UNMARKED. |
| 159 | Rælingstunnelen | Akershus | 1800m | ? | Go via Strømsveien |
| E39 | Refstiheia | | 400m | Yes | |
| E10 | Rekvika | Nordland | 500m | Yes | |
| 152 | Rikåstunnelen | Akershus | 256m | ? | Go via the local road through Kolbotn centre. |
| E6 | Ringnestunnelen | Akershus | 335m | ? | Go via the old Mosse road. |
![]() | 650 | Ringsettunnelen | Møre og Romsdal | 592m | Yes | None. |
| E16 | Risnes | Hordaland | 1718m | ? | Go around the tunnel. |
| E16 | Romslo | Hordaland | 605m | ? | Go around the tunnel. |
| E10 | Rorvikskardet | Nordland | 500m | Yes | |
| 585 | Rothaugen | Hordaland | 195m | ? | Go around the tunnel. |
| 651 | Rotsethorntunnelen | Møre og Romsdal | 4000m | Yes | The Gule Sider map shows a possible alternative via a small road along side the fjord via Løviknes, Greivnes and Andanset, although this cannot be confirmed as yet. (Jon) |
| E134 | Røldal | Hordaland | 4657m | ? | Take the old road over Røldal (summer only). |
| 32 | Rønningentunnelen | Vestfold | 105m | ? | Go via the local road. |
| 4 | Røstetunnelen | Oppland | 1100m | ? | Go via the Fv 16 Stryken - Sand, Roa. |
| E6 | Ryentunnelen | Oslo | 154m | ? | Take the cycle path. |
| 820 | Ryggedalen | Nordland | 1621m | Yes | |
| E39 | Sandvik | Hordaland | 394m | ? | Go around the tunnel. |
| E16 | Sætre | Hordaland | 720m | ? | Go around the tunnel. |
| E134 | Seljestad | Hordaland | 1272m | ? | Take the old road over Røldal (summer only). |
| E39/E16 | Selvik | Hordaland | 124m | ? | Go around the tunnel. |
| 862 side road | Sentrumtangenten | Troms | 1628m | ? | Go on the local road. |
| 85 | Sigerfjord | Nordland | @ 2180m | ? | |
| 17 | Sila | Nordland | 2882m | Yes | |
 | 17 | Sjona | Nordland | 2796m | Yes | |
| 830 | Sjønståfjell | Nordland | | ? | |
| 862 | Skaland | Nordland | 1890m | Poor | A big detour to the south. Follow your map. |
| E16 | Skaret | Buskerud | 465m | ? | Go via the Fv155 + cycle path. |
| E6 | Skarpsnotunnelen | Hedmark | 300m | ? | Go via the local road. |
| 13 | Skarvabjørg | Hordaland | 122m | ? | Go around the tunnel. |
| E69 | Skarvberget | Finnmark | 3km | Poorly lit. | |
| E134 | Skjoldavik | Rogaland | 140m | ? | Take the road around the tunnel. |
| 36 | Slåttekås | Telemark | 310m | ? | Go via the local road. |
| 308 | Slottsfjelltunnelen | Vestfold | 235m | ? | Go through Tønsberg centre. |
| New E10 (Lofast) | Sløverfjord | Nordland | @ 3390m | ? | |
| 150 | Smestadtunnelen | Oslo | 501m | ? | Go via the local road/ cycle path |
| E6 | Smiehagen | Akershus | 892m | ? | Go via Årungen. |
| 44 | Smørskjerbukta | Rogaland | 100m | None | |
