Second to this is the Great Western Greenway, an off-road trail which which spans 42 km between Westport and Achill Sound. Formerly the train track, it was rejuvenated into an off-road walking and cycling trail in 2011. Each section of the Greenway brings its own pleasures. From Westport to Newport (some 11 km) the route is pastoral, gentle landscape populated by wild flowers and lovely streams. From Newport to Mulranny is slightly more challenging, at 18-km with beautiful views as the sea reveals itself along the way. For the final leg of the Greenway, you leave Mulranny, behind the Mulranny Park Hotel and descend through an atmospheric woodland which continues for a short distance until the vistas which open out before you--distinctive green and brown undulating hills against a backdrop of dark mountains and the Atlantic Ocean lapping against the jagged edged coast-- are nothing short of spectacular.
National Loop walks are dotted around the county and some of them incorporate forests and hillsides. The Letterkeen Loop walk extends for 12 km and is fairly difficult as the path follows an old cattle track through forestry and ascends to over 300 metres at its steepest point in the Nephin Beg mountain range. Walkers should be prepared for rocky terrain and wet slopes for around three and a half hours. The Tourmakeady Forest Walk is a manageable 6km walk through the Millennium Forest alongside the Glensaul River and culminates in a secluded cove with the beautiful Tourmakeady Waterfall. The woodland is rich and varied with oak, ash, hazel, birch and alder trees, as well as badgers, foxes, and a great range of birds, making it a lovely spot for picnic.
If group walking excites you more, then the Burrishoole Walking Festival is a three day event held annually. For a nominal fee you get food and entertainment as well as a unique walking experience through Newport, Derrada, Tiernaur & Mulranny with a choice of high and low level walks.
Further north in Ballycastle you will find the fresh atlantic air refreshing while you take in the view of 600 million year old rock formations known as the Stags of Broadhaven. The Sralagagh Loop Walk begins in Ballycastle and covers nine and a half kilometres. Lanes and sandy path make this a fairly dry walk which is also suited to mountain biking.
Near Belmullet in the Erris peninsula, a coastal route runs from the Cross Abbey ruins along the beach. This is a leisurely walk and it best walked at low tide. Stretching for two and a half kilometres, you can follow the trail across sand dunes and over to Cross Lake where views of swans and wildlife on the lake as well as the Iniskea islands beyond are spectacular. www.mayowalks.ie offers a comprehensive guide to walking in Mayo.