Another image from Ebay
Can somebody identify the gun and the batterie ? 28cm SK L50 ??

Sturm78
Thank you for your answer, ludvig.ludvig wrote
Lookd as MKB 3 513 with 3 x 28 cm SKL 45 notice Flachbettung + side armour + snow
Hi,
The sources are unclear, but the guns are probably Krupp 210/40, bought by Turks before WWI. Four piece were installed at two batteries at Karabournou fortress near Thessaloniki (now Angelochori, Cape Magelo Emvolo). It is sure they were produced fort Turks, because there are photos of Arabic letters on the gun. The batteries were reused by the Greeks.
Hi Sturm. The guns were probably installed right in the Thessaloniki batteries and captured by Greeks during the First Balcan War. Then they remained at Greek service at their original positions. The guns were modern, with hydraulic recoil mechanism. It was next generation of weapons, comparing to most of the Turhish Krupp guns a howitzers, installed around Dardanelles and Bosphorus.