Watch List notes:

Caria, Antiochia ad Maeandrum. Gallienus. A.D. 253-268. AE 37 medallion (26.92 mm, 19.50 g, 6 h). Ca. A.D. 260. Very Rare. AV KA ΠΟ Γ AΛΛI HNOC, helmeted and cuirassed bust left, holding shield and spear / ANTIOXEΩΝ, six-arched bridge with guard rails across the Maeander River; triple-bayed triumphal arch at one end; figure of Maeander River reclining left above guard rail. SNG von Aulock 2430; SNG Munchen 92. Good VF for type, pourous. Rare in this condition and strike!. 

From the Virginia Collection of Architectural Types; Ex Numismatik Naumann. 

After the defeat of Valerian I by the Persians, the autocrat, Gallienus won the bridge over the Maeander River, which was very important for supplies on the eastern front.