Tantallon Castle is a ruined medieval fortress atop a promontory opposite the Bass Rock, looking out onto the Firth of Forth. It was built in the mid 14th century by William Douglas and was the last medieval curtain wall castle to be constructed in Scotland.
Despite several sieges, Tantallon remained the property of Douglas descendants for much of its history. It was besieged by King James IV in 1491, and again by his successor James V in 1527, when extensive damage was done. Tantallon saw action in the First Bishops' War in 1639, and again during Oliver Cromwell's invasion of Scotland in 1651, when it was once more severely damaged.
Tantallon is a unique construction within Scotland, the defences comprising only a single large wall securing a coastal promontory. The south-east, north-east, and north-west approaches are naturally defended by steep sea cliffs and were only ever protected by relatively small defensive walls. To the southwest, a massive curtain wall blocks off the end of the promontory, which forms the inner courtyard. The curtain wall is built of the local red sandstone and has a tower at each end and a heavily fortified gatehouse in the centre, all of which provided residential accommodation.
The ruin is today in the care of Historic Environment Scotland and open to the public.
References:Herceg Novi was founded (on a former small fishing village, existing since Roman Empire times) as a fortress in 1382 by first Bosnian King Stjepan Tvrtko I and was called Sveti Stefan or Castelnuovo. The Turks conquered Herceg Novi in 1482, and ruled for 200 years, until 1687. However, there was a short pause between 1538 and 1539 when it was held by the Spaniards before they were defeated in the Siege of Castelnuovo. Turkey ruled again until 1687, from then until 1797, the town was ruled by the Venetian Republic.
The Herceg Novi old town is amazing. It is on a fairly steep hill that leads all the way down to the sea. Wandering through the small stairways to the various plazas and fortresses is a many hour adventure.