Alex Roddie heads to the rolling high point of Northumberland, dodging the bogs and looking for a place called the Bizzle.

Height: 815m

Personality: Sprawling, rounded, complicated, and with a reputation for savage weather, the Cheviot is a muscle-bound unit of a mountain peering over the border from England into Scotland. It's the last major climb on the Pennine Way and the highest point in Northumberland.

What's in a name? Some say The Cheviot, others simply Cheviot. The origin of the name is unknown, although it's thought to be Celtic. In The Brittonic Language in the Old North, Alan G. James speculated that 'Cheviot' may derive from the Celtic prefix *ceμ- ('ridge'), and the second syllable may have been influenced by the Old English ġeat ('gate' or 'gap').

So do you have to climb it if you're doing the Pennine Way? The Cheviot's summit is a short detour – and 72m climb – from the Way. Some walkers will take the ascent in their stride, while many will understandably give it a miss; the last leg of the famous long-distance trail is tough enough without adding an extra summit.

Best route: A fine route begins from Hethpool in the College Valley and follows the beautiful College Burn almost to its source before exploring the dramatic craggy ravine of Hen Hole, just out of reach from the crowds on the Pennine Way. This gorge is full of waterfalls, and some superb mountain rock climbing, and makes a rough and interesting route to the summit.

Most unfrequented route: A quiet circuit of the Cheviot from the eastern side begins at the small village of Linhope in the Breamish Valley. After walking through woods alongside the Linhope Burn to Linhope Spout, a beautiful waterfall, the route climbs steep slops to the 714m summit of Hedgehope Hill. Open ridgelines lead to the peat hags of Comb Fell (652m) and Cairn Hill (777m), where the route joins the extension from the Pennine Way.

Summit landmarks: On the summit you'll find a well-constructed flagstone path weaving in between the peat hags, leading to a distinctive summit monument: a conventional trig pillar perched atop a square-section plinth. There isn't much of a view from the actual summit, thanks to the flat terrain, but the views from the edges of the plateau are extensive thanks to the fell's considerable height. The view north-east down the length of Harthope Burn is particularly striking from some angles.

A magnet for plane crashes: Thanks in part to the Cheviot's height, this fell has seen a number of plane crashes over the years. In 1944, a B-17 bomber laden with bombs came to grief just north of the summit. Two local shepherds found four survivors; three more found their own way off the hill. Two were killed in the crash. To this day, the remains of the bomber can be seen on the plateau.

Hidden gem: On the secluded northern side of the Cheviot you'll find a feature named, delightfully, 'the Bizzle' – a steep cleft between rocky crags. The valley is occasionally used as a route of ascent and is well worth a visit. Among the many recorded rock climbs on these crags is an obscure Very Difficult route known as Bizzle Chimney, put up in 1899. This is the oldest recorded climb in Northumberland.

Any winter climbs in the area? The Bizzle Crags are host to several low-grade winter routes. The Bizzle Burn itself is recorded as a Grade II/III climb when in condition, and there are opportunities for simple climbs on steep snow elsewhere on the Cheviot's northern side.

Where to stay? Mounthooly Bunkhouse at the head of the College Valley is perfectly situated for the Cheviot.

Local pub: The Border Hotel, Kirk Yetholm, is the classic hiker's pub in the area, and the traditional spot for finishing the Pennine Way.