Work to preserve an historic Guernsey chapel has begun.
St Apolline's Chapel was built in the 14th Century
The structure of St Apolline's Chapel in St Saviours will be assessed as part of the development of a conservation plan for the 14th Century building.
Concern was raised two years ago that murals inside the chapel were at risk from damp.
As part of the project, a hand-sized stone will be removed from one of the walls to find out how the building was constructed and how porous it is.
Two holes will also be dug to check the condition of the walls below ground level.
The work is being supervised by architect Richard Andrews, from Wessex Archaeology, the organisation which is developing the plan for the site.
The chapel was built in the 1300s and was the first building in the island to be recognised as an ancient monument.
The ecumenical chapel is used for baptisms and there is a well-attended service in the building every Thursday morning.