When I visit Sister Teresa, the locally-born taxi driver has only a rough idea of where the convent is situated, although it occupies a historic Tudor house and is officially signposted. There is a guesthouse and a public chapel (the sisters themselves use a private chapel within their enclosure). To help finance life at Quidenham, the nuns sell handmade cards, and one sister also sells her own paintings. Sister Teresa undertakes needlepoint commissions. They venture into nearby Norwich only for medical appointments "or to buy decent shoes", and the sisters have very little interaction with the lay community. In a diocese with a tiny Catholic community and a poor record of church attendance, the convent has all but sunk into the silent Norfolk countryside.

In the internet age, you might presume it would be easy for both cloistered and non-cloistered nuns alike to connect with the wider world, and many have made a fair attempt at it. One Benedictine house in Oxford has started offering online "retreats" as a way of providing spiritual succour while raising revenue for structural repairs which would allow it to provide accommodation for visitors. But while the internet may theoretically aid access to information on convents, individuals can't search for what they don't know is there. Advertising retreats can also inadvertently attract vulnerable people who would fare better at a mental health clinic with counselling care, rather than in an isolated and silent setting.

Educating people about their work is easier for the more visible apostolic orders. One such is the Franciscan Missionary Sisters  based in Littlehampton, West Sussex, which has just celebrated its 100th anniversary. Established originally to teach and care for orphaned children, the order provides teaching, social work and care of the elderly at five houses across the country. At the house generalate, 20 sisters live in a purpose-built 1960s block on the site of the original, rather more elegant convent, which was damaged during World War II. Behind its mundane exterior, the house bustles with convent-lay collaborations: a nearby school uses its kitchen for a regular cooking competition, Sister Anastasia runs a scripture group which is well attended by Catholics and non-Catholics of all ages, and each month sees some innovative fundraising enterprise. 

While many of the nuns are in their seventies and eighties, their zest for life and mischievous sense of humour is palpable — and contagious. Over lunch, they regale me with the story of the float they decorated and rode on for the annual local carnival. "We were right behind the belly-dancers. Sister Clare wasn't flashing her tummy but you should have seen her wriggling around."

"And it was terrible Sister, wasn't it?" intones 70-year-old Sister Eugene in mock condemnation, before winking at me.