Before the introduction of Christianity, Granarwælle was a focal point in Heda region and there was probably a place of worship here. Behind the chancel in Nikolai Church there is a rune stone with a Christian inscription from 1050. It is older than the churches and is a testament to the significance of the region far back in time.
The Sister Churches have been a landmark since they were built almost 800 years ago, and there are legends and stories about their origin. The high church wall and the tower in the churchyard, as well as the Stone House, have been central to recent research into the churches’ history.
- Maria Church is dedicated to the Virgin Mary and was built in 1150, and the slightly larger Nikolai Church was built about 100 years later and is dedicated to St Nicholas, the patron saint of children and protector of travellers. In the Middle Ages it was not uncommon for churches to be built beside each other, while having different functions and tasks. Maria Church with its Romanesque and Gothic styles is known to have functioned as a chapel and been in less use than Nikolai Church. While Nikolai Church was the county church for Hadeland, Maria Church was the church for the parish of Gran.
In the Gran parish register for 1732 there is a story of two sisters who built a church each.
- The southerly Maria Church was built by the elder sister, while the northerly Nikolai Church was built by the younger sister.
- Another story goes that two sisters fell in love with the same priest and each built a place of worship for him.
- A third legend tells of two sisters who went to Mass but had fallen out and wanted to be buried in different churches when they died.
There were ties between the guest house, vicarage and Sister Churches. In 1722–23 when the Danish king decided that Norwegian rural churches were to be sold, Sheriff Gregers P. Granavolden was one of the two people who bought the Sister Churches. Together with the dean of the vicarage and four others, he also donated a cabinet organ to Nikolai Church. Today it is in the Norsk Folkemuseum and is a national treasure. Around 1830–40, when Siri and Niels Olsen owned the guest house, refreshments were served both before and after church at the guest house. Siri rented out bridal finery and a traditional bridal crown to the bride. The guest house and church worked together when weddings took place.
The churches no longer have the same place and importance in people’s lives as before, but the Sister Churches provide a dignified setting that is still important in marking life’s events.