VISITORS will be able to trace the religious history of a hillside village, tour a prison, visit a courthouse and even get a bird's eye view of their towns as hundreds of venues open free of charge.

Mount Grace Priory, near Osmotherley, North Yorkshire is running wildlife trails, a spot-the-stoat competition and bird-watching sessions.

The monastery dates from 1398 and now has a reconstructed version of a monk's cell.

At 4pm tomorrow, a choral group from Exeter will perform vespers and lead a procession from the monk's cell to the church.

The priory is open between 10am and 6pm from today until Sunday.

The Lady Chapel high on the hills above Mount Grace is also opening on Saturday and Sunday, from 1pm to 5pm.

It was established before the Reformation as a hermitage, but fell into ruin in the 16th Century. It was later rebuilt and reopened in 1961.

Our Lady of Mount Grace chapel will be open from 1pm to 5pm on Saturday and Sunday.

It was given to the Franciscan Friars in 1655 when Catholic chapels were illegal, and is hidden in the roof of the Old Hall.

Another church -one of the country's oldest -will invite visitors in.

Escomb Saxon Church, just outside Bishop Auckland, County Durham, was constructed in about 670AD.

It is one of the finest examples of early Christian architecture in Northern Europe, and volunteers are hosting an open day from 2pm to 6pm on Sunday.

One of the highlights of the afternoon will be a guided walk around the village, which will last about an hour.

Those wishing to take part should meet at the church at 4pm.

Light refreshments will be available throughout the day, which will be brought to a fitting climax with songs of praise at 6pm.

People have the chance to see behind the scenes at Durham Crown Court when it opens.

The Grade II listed building next to Durham Prison, in Old Elvet, has been extremely popular during previous open days.

Free tours of the building will be available from 10.30am to 3.30pm on Saturday.

The court was designed in a classical style in about 1811 by Ignatius Bonomi and George Moneypenny and built from local sandstone.

It was originally the local Assizes Court and in its history has heard celebrated trials such as that of the West Auckland mass poisoner Mary Ann Cotton, who was hanged in the prison in 1873.

Visitors will be shown the building's two courtrooms, cells and jury rooms.

About 30 attractions in the Durham City area are taking part in the open days.

A programme is available from the Tourist Information Centre, Millennium Place, Claypath and the Durham Heritage Museum, in the former St Mary-le-Bow Church, North Bailey, which is hosting an exhibition on the featured properties.

Information is also available by calling the council's heritage and design team on 0191-301 8726 or from the council's website at www.durham city.gov.uk

Darlington Railway Centre and Museum is also taking part in the open days.

The museum is housed in an original 1842 Darlington and Stockton Railway station and describes the history of railways in Darlington and the North-East.

One of its prized possessions is Stephenson's Locomotion.

As well as the usual sights, visitors taking part in the Heritage Open Days tour over the weekend can see railway sheds and archive material not normally available to the public.

On Teesside, visitors will be able to scale Middlesbrough's Transporter Bridge to get a bird's eye view of the town.

The landmark is the only working transporter bridge of its kind in England.

Visitors will also be able to view the winding house and visitor centre, which offers interactive information and games about the history of the bridge.

Access to top of bridge will be at 30-minute intervals throughout the day. Unfortunately, there will be no access to the top walkway for disabled people and there is an age limit of six years for children wanting to scale the heights. The bridge, opened by Prince Arthur of Connaught in 1911, is a cross between a ferry and a bridge, where vehicles are transported across the river by means of a moving car, which is capable of carrying 600 people or nine vehicles.

The visitor centre is open between 9.30am and 4.30pm on Saturday. People can turn up at the event, but fares will be charged for those wishing to travel on the gondola.