In 2002 a team of American surveyors, using sophisticated depth-sounding equipment, carried out a survey of Rennes Church and confidently asserted that there was a large void under the nave – probably a vaulted crypt. The question is – how was it accessed?

Excavations had already been authorised in the church in 1967 after a letter had come to light, written in the early eighteenth century, by the uncle of the Abbé Bigou (see the previous blog) which referred to a crypt and said that the entrance had been blocked up.

The professor who carried out the excavations reported that he had discovered the beginning of three passages leading downwards below the church. One was in the north wall of the church, being a staircase beneath the steps within the wall which lead up to the pulpit. The second was in a “little structure off the sacristy”. The third wasn’t described and, oddly, the excavators blocked up the entrances they had found and apparently went no further with their exploration. One wonders what influenced their change of heart.

Of the three possible entrances which have been put forward, the most interesting would appear to be in the “secret room” (referred to as an isoloir) which Saunière built off the sacristy in 1894. It is believed that the only entrance to this room is through the back of the cupboards which are built against its eastern wall. Unfortunately public access is not permitted to the isoloir or even to the sacristy and I cannot find a report from anyone who has been in either room.

However it is recorded that the priest had been seen to leave the church and go into the sacristy (which has no outside door) at the end of the service and appear outside a few minutes later without going back through the church which was still occupied by a number of the congregation. He obviously had a secret exit route.

The photo shows a model of the church viewed from the south which is not quite accurate. The sacristy is the lean-to structure with the window in the roof. The “secret room” is the small quadrant-shaped building to its right which is actually linked to it. This room could easily house a curved staircase leading down into the crypt.

Next week I will discuss what Saunière may have discovered in the crypt.