Walk of the Month: Follow the flight of the red kites in Durham

Majestic bird life, old tramways, sunken lanes and an 18th-century folly await Mark Rowe on the outskirts of Newcastle

You can't mistake a red kite for any other bird. From a distance they resemble model aeroplanes, their forked tail working like a rudder, jerking, tilting, from side to side. And they are one of the great environmental success stories of recent years, now found up and down the country, including semi-urban areas, such as the outskirts of Newcastle. Right on cue, I see one as soon as I step off the bus after a 15-minute ride from the city centre.

Kites were reintroduced to the North-east in 2004, the last phase of a UK-wide project that has rejuvenated the birds' fortunes. Red kites were once ubiquitous around Britain, but persecution and poisoning reduced them to a small rump in Mid Wales. They look enormous, which historically has been their undoing as farmers and gamekeepers believe them capable of carrying off sheep and game birds.

The reality, says Vicky Catley, a National Trust ranger who accompanies me for the first part of the Red Kite Trail, is rather different: that large parcel of feathers is misleading. "In the air, they look like massive raptors, but when you hold one, it is so light, it's no more than a bag of sugar," she says, almost cooing at the thought of them. "They are all feathers, that's why they are such good flyers. When the sun is right, you get that amazing flash of red on their wings."

Their appetite for fluffy mammals is also misplaced: they prefer carrion and worms, and even a squirrel is heavy enough to reduce getting airborne to a struggle. Happily, their reintroduction has been welcomed by most locals and kites can often be seen picking on Sunday roast carcasses left out for them in back gardens.

The birds are part of a wider environmental success story. The River Derwent (not to be confused with the Derwents of the Peak or Lake Districts) and its countryside were blighted for centuries, first by ironworks then by coal. Some of the scenic Lilliputian hills I walk past, planted with young ash and rowan, are moulded from slag heaps left over from the coking industry.

There are other man-made imprints. The path later picks up an old tramway and traverses a spectacular nine-arched viaduct over the Derwent. To the east stands a 40m tower, a folly put up by the local estate owners, the Bowes-Lyon family, which they called, a little vaingloriously, the column to liberty. Close by, stands a ruined pile, all that remains of the family home.

These pinpricks look distant, but I'm soon close enough to briefly detour to the family's old Gibside estate, now owned by the National Trust. The 18th-century landscape garden is structured around viewpoints and sightlines, of which the most dramatic feature is the mile-long grass avenue lined with English and Turkish oaks. In between, is the old house. I'm struck by its unusual dimensions: it is deliberately long so as to impress from afar, but when I see it side-on it's barely thicker than a cowboy town film set. I grab a sandwich at Gibside's café since, apart from one pub, there's nowhere else to break the walk before you return to Derwenthaugh car park.

From Gibside, the path follows the old tramway, before crossing the River Derwent for the umpteenth time in the hamlet of Lintzford. This is a busy spot for the river, with streams emerging from culverts picturesquely beneath the flanks of the handsome stone houses. From here, the path begins a series of climbs into Chopwell Wood, where there is a viewing point by an ornate carving of a red kite. I'm suddenly quite high up and the kites fly at eye level, hanging like giant mosquitoes in the air. The trail winds further up the wood, eventually emerging behind allotments and leading to a churchyard blessed with a wide-angle lens view on the countryside. It's one of those unsettling cemeteries with conspicuously large yet-to-be-used spaces, rather like an oversized car park, empty today, but designed with future demand in mind.

Behind the churchyard the path crosses some rough pasture grazed by cows, where the recently ploughed land lays on a banquet for those worm-loving red kites. There are brief views down the Tyne before I drop down into Spen Banks Wood following sunken lanes, old tramways and winding shaded tracks that seem to have no end. It's glorious: the woods are silent apart from the intermittent drill-like echo of a woodpecker and occasionally the canopy thins out enough for views over farmland.

Finally, the path breaks cover on to Barlow Fell where I can pick out both the Tyne Bridge and the Gateshead Millennium (or "winking eye") Bridge. The Gibside landmarks are to the south. The view ahead is the most thrilling: due north towards the Cheviots and the open plains of Northumberland. You can drink in this view in a more literal sense at the Black Horse Inn in Barlow which has the best of the designated viewing stations for the red kite (at the end of this trail, walk for 100 metres up the road where another good pub has been renamed after the eponymous bird).

The lonely winding path keeps me trundling along and towards the end of the walk, as I drop down under yet another gorgeous canopy sheltering a sunken path, I realise that I haven't seen another person for the best part of three hours. The countryside has been empty, apart, of course, from the red kites.

Directions

Start/Finish Derwenthaugh car park, near Winlaton Mill, west of the Metrocentre on the A694

Distance 12.5 miles/20km, including detour to Gibside

Time Five hours

OS Maps Explorer 216 Newcastle & Tyne, Explorer 307 Consett and Derwent Reservoir. Buses 45, 46 and 47 run from Newcastle city centre to the start of this walk.

Route description The circular walk is well signposted by red kite waymarkers. Full details can be found at visitnortheastengland.com and search for "Red Kite Trail".

Getting there Mark Rowe travelled with Cross Country trains (crosscountrytrains.co.uk) which serves Newcastle from the Midlands and Scotland. Newcastle is also served by East Coast (eastcoast.co.uk) from London King's Cross, Yorkshire and Scotland, and by First TransPennine from York, Leeds and Manchester.

Staying there Mark Rowe stayed at Hotel Indigo Newcastle (0191 300 9222; hotelindigonewcastle.co.uk). Doubles start at £109, room only.

More information newcastlegateshead.com; nationaltrust.org.uk/gibside