When Clifton Webb meets Sophia Loren at the restaurant, it is 7 pm. Then he goes on a trip into the mountains which must have taken a few hours. During his trip, as well as on his arrival, it is bright sunlight.
When Dr Calder (Alan Ladd) is riding in the truck with a large slab of carved stone in the back, the vehicle approaches the Acropolis from the north side, passing the Stoa of Attalos. In the very next scene, the truck is approaching the entrance from the south side. There is no street that directly connects the area of the Stoa of Attalos to approaches to the entrance of the Acropolis.
The writing on the signpost "Meteora 4 km" Webb passes on his way to the monastery is in Latin letters instead of Greek ones.
Rhif is drinking wine from a "bota" bag, the way Spaniards do. Greeks never to that.