The gate of Armenon or Larmenon, is one of the monuments that signals the historic succession in the area of Stiron. It is preserved on top of Ayios Nikolaos of Diakofti (height 450 m.), in the mountain Kliosi in Styra of Southern Evia.
The gate, that constitutes also the emblem of Municipality of Styreon, is an impressive megalithic construction made with Cyclopean Stones, while we can note on the left and right side of it the remains of ancient cyclopean wall.
In later years, Western Europeans built a castle on top of the wall of the ancient citadel of Styron. In early 1300 A.D. it is occupied by Catalans, which they sell the fortress in 1373 to the Enetians. Its use continues after the occupation of Evia in 1470 from the Ottomans.
An important monument, highly visitable, that points out the importance of the area.