Crucifixion of St Peter: Romanesque capital, abbey church of St-Pierre, Moissac. 
The story goes that, at Peter’s crucifixion, he requested to be hung upside down, as he didn’t feel worthy to be crucified in the same manner as Christ (after that whole “denying three times” deal, he wasn’t far wrong). 
Around the top of the capital, you can see the TRE of “PETR[A]E” followed by MARTIRIO then SCS for SANCTUS.

Crucifixion of St Peter: Romanesque capital, abbey church of St-Pierre, Moissac. 

The story goes that, at Peter’s crucifixion, he requested to be hung upside down, as he didn’t feel worthy to be crucified in the same manner as Christ (after that whole “denying three times” deal, he wasn’t far wrong). 

Around the top of the capital, you can see the TRE of “PETR[A]E” followed by MARTIRIO then SCS for SANCTUS.