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The Cob Causeway – Harlech Castle loop from Pensarn

The Cob Causeway – Harlech Castle loop from Pensarn

Hard

riders

The Cob Causeway – Harlech Castle loop from Pensarn

03:57

83.5km

960m

Road cycling

Hard road ride. Very good fitness required. Some segments of this route may be unpaved and difficult to ride. The starting point of the route is accessible with public transport.

Last updated: February 27, 2026

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The surface for a segment of your route may not be suitable

Some segments of your route comprise a surface that may not be suitable for your chosen sport.

After 77.5 km for 347 m

Waypoints

Start point

Train Station

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21.2 km

Caer Fedw

Forest

24.2 km

Pont Aberglaslyn

Highlight • Viewpoint

The bridge was probably built in the 17th century and then radically rebuilt and widened in 1795-1796. As with many older bridges, folk tales claimed that the bridge was built …

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27.7 km

View of Beddgelert and the Glaslyn River

Highlight • Viewpoint

Take care in winter months but seeing the area is wonderful watch out for cattle grids

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34.3 km

Drws y Coed Climb

Highlight (Segment) • Climb

A 4.3km climb in Dyffryn Nantlle with a deceptive average gradient of 3.3% with the final section closer to the maximum gradient of 12.4%.

A 4.3km climb in Dyffryn Nantlle …

Translated by Google •

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39.7 km

View of Snowdon (Yr Wyddfa) Across Llyn Nantlle Uchaf

Highlight • Viewpoint

Nantle Valley is well known for its mountains and ridge. A lot of historic settlements and slate mining. Stunning views of Snowdonia. Road surface is good watch out for sheep …

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52.1 km

Quiet Country Lane with Cows

Highlight • Cycleway

Nice alternative to the bigger roads. Surface is pretty good in the whole.

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53.8 km

Country Road with Views of Craig-y-garn

Highlight • Viewpoint

The little road between the A487 at Dolbenmaen in the south and Garndolbenmaen in the north. A high point of about 120m means great views towards the sea in the …

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64.4 km

The Cob Causeway

Highlight (Segment) • Bridge

This mile-long causeway crosses River Glaslyn as it reaches the estuary. Opened in 1811, this causeway carries the Ffestiniog Railway as well as an A road and a cycle path. …

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77.6 km

Coed Carreg-wen

Forest

80.1 km

Harlech Castle

Highlight • Viewpoint

Against stiff competition from Conwy, Caernarfon and Beaumaris, this is probably the most spectacular setting for an Edward I castle in North Wales. All four are recognized as World Heritage …

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83.5 km

End point

Train Station

Way Types & Surfaces

Way Types

41.6 km

34.5 km

5.19 km

1.97 km

350 m

< 100 m

Surfaces

77.3 km

5.89 km

350 m

< 100 m

Elevation

Nothing selected – click and drag below to see the stats for a specific part of the route.

Highest point (240 m)

Lowest point (0 m)

Weather

Tuesday 12 May

14°C

8°C

62 %

Additional weather tips

Max wind speed: 28.0 km/h

to get more detailed weather forecasts along your route

Our route recommendations are based on thousands of hikes, rides, and runs completed by other people on komoot.

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The Cob Causeway – Harlech Castle loop from Pensarn

Pont Aberglaslyn

View of Beddgelert and the Glaslyn River

Drws y Coed Climb

View of Snowdon (Yr Wyddfa) Across Llyn Nantlle Uchaf

Quiet Country Lane with Cows

Country Road with Views of Craig-y-garn

The Cob Causeway

Harlech Castle

Nearby routes

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