Lon Las Menai & Lon Eifion

This scenic route from Caernarfon to Bryncir runs alongside the Welsh Highland Railway and offers wonderful views of Caernarfon Bay and Snowdonia. Starting near the impressive Caernarfon Castle, the traffic-free route climbs 152m (500ft) over 10 miles to its highest point, a radio mast south of Penygroes, before a gentle downhill stretch to the village of Bryncir.

Route Description

This 4-mile section of dismantled railway through broadleaf woodland links Caernarfon with the old slate harbour of Port Dinorwig (Y Felinheli). There are views of the Menai Strait and across the water to the island of Anglesey. 

The Menai Strait is 13 miles long and between 200 yards and 1 mile wide. Near Bangor the strait is crossed by two famous bridges: the Menai Suspension Bridge was built by Thomas Telford in 1819-26 and the Britannia Bridge, which was originally a tubular railway bridge built by Robert Stephenson. This was destroyed by fire in 1970 and a new bridge was built in 1972 with an additional deck for the A5 road. Before these bridges, crossings were made by ferry but cattle were forced to swim.

Things to see and do

  • Menai Strait
  • Views of Anglesey
  • Caernarfon Castle

Please note

We have taken all responsible steps to ensure that these routes are safe and achievable by people with a reasonable level of fitness. However, all outdoor activities involve a degree of risk. To the extent permitted by law, Sustrans accepts no responsibility for any accidents or injury resulting from following these routes. Walking and cycling routes change over time. Weather conditions may also affect path surfaces. Please use your own judgement when using the routes based upon the weather and the ability, experience and confidence levels of those in your group.

Please help us protect this route

Lon Las Menai & Lon Eifion is part of the National Cycle Network, cared for by Sustrans. Your donation today will help keep the Network safe and open for everyone to enjoy

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