There’s a door on St Christopher Street that most people walk straight past. Behind it lies a world that was completely sealed off from the public for over 400 years – and it’s one of the most emotional experiences Valletta has to offer.

Mysterium Fidei (meaning “mystery of faith”) is set within St Catherine’s Monastery, founded in 1575 as a refuge for orphaned girls. The stones used to build the monastery above were quarried from beneath the site itself, and those underground chambers now form the building you can walk through today. A small number of cloistered Augustinian nuns still live in the upper floors, which remain closed. What’s open to visitors is the ground level, and it’s plenty to consider.

What you’ll find inside
The route takes you through the rooms where the nuns lived out their entire lives. It’s the details that stay with you:
- Large metal washbasins, which would have been given as a dowry
- The furnace and bakery
- A central well, used to draw water from the rock below
- A curious bell system that called individual sisters, each with her own unique call pattern
- Sleeping quarters, sewing rooms and craft workshops
- The crypt, its walls lined with photographs of sisters who have passed
- The chapel


The audio tour, available via the Mysterium Fidei app, works well and covers most rooms. Signage is in English throughout, with the app offering additional languages.
At the centre of the complex is the secret garden, a small enclosed courtyard open for the first time in four centuries. The resident cats are friendly and sometimes accompany visitors on their circuit.


The women behind the walls
To make this visit truly resonate, you must imagine the daily life of a sister residing within these walls. Reading through the anonymised stories of the women who came to live here, you start to understand that not all of them chose this life. Some were sent by families who found them inconvenient: for being outspoken, for being victims of assault, for failing to conform with society’s expectations. Many of these women would never leave. The many sisters’ photographs found in the crypt, row after row of faces, asks a quiet question with no easy answer.

The cloistered life
These women worked hard. Running along the walls are large stone washbasins built directly into the limestone, fed by a clever water system that piped boiled water from the ovens into the basins nearby. Laundry was a daily, physical labour, not a chore to be finished quickly. Beyond the labour of laundry, the sisters cooked, sewed, made candles and tiles, tended the garden and kept animals. Their days were ordered by prayer and manual work. They subsisted on meagre food and owned almost nothing. Standing in these bare rooms, you are struck by how challenging their lives must have been.
The experience leaves you with a profound sense of what it means to strip a life back to almost nothing – no luxuries, no contact with the outside world, no freedom to leave. Whether the women who lived here found peace within those walls, you can only hope.

Good to know
- Location: 140 St Christopher Street, Valletta
- Opening hours: Monday to Saturday, 10:00 to 17:00
- Tickets: Around €10; a combo ticket with the Black Friars Experience at St Dominic’s Priory is available and worth considering if you have a full day in Valletta
- Visit length: Allow 45 minutes to an hour
- Tip: Afternoons midweek tend to be quieter; mornings in peak season can get busy
Mysterium Fidei is an easy walk from anywhere in Valletta. If you’re spending a day in the capital, it makes an ideal counterpoint to the grandeur of St John’s Co-Cathedral – something smaller, quieter, and harder to shake.