Chung-yan C.
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To get a good look of the interior of the rock churches, which Matera is famous for, you have the option to buy a single ticket for 4 euro or a combined ticket of 3 churches for 8 euros. The two-ticket option at 7 euro makes no sense.
If you want just pick one from the three, this will be my choice. It may not be an obvious choice. Madonna de Idris and San Giovanni is the more famous one among the three.
But in fact if what you want is to see the interior and understand better of the rock church history, then Saint Lucia and Malve is special.
First it is the oldest in Matera- tracing back to the 9the century! The frescos inside ranging from 11th to 16th century and you can see clearly the Byzantine influences. The church is small but the frescos are more numerous and well preserved.
Also here you can see clearly the structural changes happened over time. It was converted into a house during the overpopulation and poverty-stricken “dark age” of Matera. Part of the church was modified for this for two families to live in. The front part was converted to a kitchen and restored back. This gives you a visual history of the rise and fall and the reemergence of Matera. Madonna de Idris is magnificent from outside and occupy a great location. You can simply visit it and take photos outside the church if time or budget is a concern.
San Pietro has a very interesting crypt. It is really worthy 8 euro to get all three but if only picking one, Santa Lucia and Malve will be my choice.
P.S. recommend to visit Casa Noha first and watch its well-made documentary film before visiting the rock churches.