A bit of attention to some old brickwork has given better access to the Monsal Trail in the Peak District. Jenny Clayton reports

'The valley is gone and now every fool in Buxton can be in Bakewell in half an hour and every fool in Bakewell in Buxton," ranted John Ruskin when a railway was first built in the 1860s through the peaceful Wye Valley, which runs through the Peak District National Park.

I'm on the Monsal Trail, which follows part of the trackbed of the former Midland Railway. For a hundred years trains thundered through here carrying passengers and freight between London and Manchester. The line was closed in 1968, the rails ripped up and sold off.

When the Peak District National Park acquired it in 1981, the park authorities created an eight and a half mile trail from Topley Pike to Coombs Viaduct. I'm here today to explore a missing link in that trail: four newly restored railway tunnels which walkers had, until recently, to detour around for safety reasons.

My walk begins at the western end at Wyedale, three miles east of Buxton. Picking my way through woods along the banks of the churning river Wye, I soon emerge into open grassland. The path leads up on to the old track by a cluster of stone cottages at Blackwell Mill and as I walk, wide views of hills and dales stretch ahead, the river below me now, winding through the valley. I pass through a railway cutting colonised by trees and bushes to reach Chee Dale, its spectacular 200ft limestone cliffs sweeping up into the sky, beloved by climbers.

Onwards, I reach one of the tunnels at Chee Tor. Once, the going was tricky here: the path was steep and slippery as it crossed the Wye via stepping stones which are often submerged in winter. But I'm being allowed to pass through this tunnel, because it is one of the four that are due to be opened to walkers, cyclists and horse riders from 25 May. It will make the Monsal Trail a more family – even pushchair- and wheelchair-friendly – walk.

I'm met at this point by my guide, Rhonda Pursglove, the Pedal Peak District project manager, to find out more. "They've been talking about opening the tunnels for years, but the funding only came through in 2010, so we've had to motor on with the engineering and deal with conservation issues as well," she tells me.

We venture into the Chee Tor tunnel, which is almost 440 yards long (400 metres) and 20ft high. It's dark and damp, but the old brickwork has been repointed and cables laid, which means it will be lit from dawn to dusk. The ground is being resurfaced in Tarmac. The whole project is costing almost £2.5m and will mark the 60th anniversary of the Peak District National Park, the first National Park to be created in the UK.

Out into the light, we follow the track forward, crossing the river by the imposing iron viaduct at Miller's Dale. This was one of the main stations with a branchline to the fashionable spa town of Buxton. We stop off at one of the original buildings, now used as a ranger's post, to talk to Garry Bacon who has been minding the Monsal Trail for many years.

He paints a picture for me of Millers Dale in yesteryear: a bustle of trains transporting milk from local farms, to the south, and bringing in coal for the nearby lime kilns; the whole place a smoke-filled hive of industry. Now the area is more likely to attract nature-lovers and geologists keen to study the limestone formed 300 million years ago, but visitors will be able to listen to reminiscences of the railway at audio posts along the trail.

Out in the car park we see a hardy family of walkers: Grandad, Mum and chubby baby cocooned in Dad's backpack, ready themselves for a hike. Perhaps not the full eight and a half miles – Millers Dale is one of the starting points along the trail for more modest circular walks.

We set off downstream towards the next tunnel at Litton Mill, a small hamlet of pale-grey stone buildings around a former cotton mill which opened in 1782. They are still cabling the Litton Tunnel when I visit, so it is dark, lit only by shafts of light from either end, but once out, we are rewarded with views as quaint as the name of the location, Water-cum-Jolly, with its meandering river, mill pond, and cowslip-strewn meadows.

The trail continues a short way to the third tunnel over the river from Cressbrook, another historic cotton mill, now developed into stylish flats. Escaping the wind, we venture through the sturdy brick and stone, blackened from smoke, and press on to Headstone Tunnel at Monsal Head.

Thousands of people would make the trip out from Manchester and Sheffield to marvel at its majesty. You can climb up to the Monsal Head Hotel for a pint, a meal, or even a bed for the night, or wander into the nearby villages of Little and Great Longstone.

I leave Rhonda and continue on alone along the trail to Hassop Station, where once goods were unloaded for the Chatsworth Estate. Today, it's a rather welcoming bookshop and café. There's another car park here, so it attracts a crowd of non-walkers, too, and you can hire bikes.

I don't make it to the end of the trail, two miles away, beyond Bakewell Station. After all, it's getting dark and those cakes in the café need some research.

Compact Facts

How to get there

There's car parking at either end and other points of the trail.The nearest railway stations are at Buxton and Matlock, from where you can get buses to near the trail's start and end.

Further information

Contact the Peak District National Park Authority (01629 816200; peakdistrict.gov.uk/monsaltrail).