Some of Rome’s least known churches house a wealth of exquisite, curious and downright bizarre treasures – everything from medieval mosaics to subterranean pagan temples

It was only after I agreed to write about my 10 favourite Roman churches that I realised the pitfalls. Many will have their own favourites, especially old Roman hands whose knowledge of the city, gained over many years of service there, is far greater than mine. And then there came the further suggestion that I should perhaps select those which were less well known.

This presents an additional hazard, deciding which are not obviously on the tourist trail. I suspect, however, that most people will pass Sant’Alfonso de’ Liguori, more or less halfway between Santa Maria Maggiore and the Lateran basilica, without a second glance. It resembles many a mid-nineteenth-century English neo-Gothic church, and was designed by a Scotsman, George Wigley. While it is a building of no great architectural merit, it houses perhaps the best known of all Marian icons, that of Our Lady of Perpetual Succour. It is in this Redemptorist church that Archbishop Vincent Nichols is Cardinal-Priest.

For true medieval Gothic one has to visit Santa Maria sopra Minerva in the Piazza della Minerva. It is the only church of its kind in Rome, though the Gothic is so overlaid with Renaissance additions that the original is now hard to discern. It is a Dominican church, and has been from the thirteenth century. For a time it was the headquarters of the Inquisition, and here Galileo was obliged to deny that the Earth went round the sun. Enshrined in a tomb before the high altar is St Catherine of Siena, the first woman Doctor of the Church, and a patron of Italy. Fra Angelico is buried in a passage to the right of the choir. Archbishop Cormac Murphy-O’Connor is the titular Cardinal-Priest.