Clan Rising
O'Brien's Castle today

Ireland · Partial ruin

O'Brien's Castle

O'Brien's Castle (Furmina Castle) is an early 15th-century rectangular tower house on Inisheer, built by a branch of the O'Brien family. The donjon contains vaulted ground-floor storage chambers, a first-floor great hall and mural stairs up to a parapet with a corbelled bartizan. The structure stands on one of the island's highest points and today survives as a partial ruin.

Photograph via Wikimedia Commons

Its prime

1400

Today

Partial ruin

As it stood in 1400

The shape it held in its prime.

A rectangular stone donjon/keep of grey limestone rubble with squared ashlar quoins at the corners, rising directly from a grassy island ridge. Tall, straight walls punctured by narrow slit windows and a small ground-level storage doorway, with a first-floor entrance originally reached by an external timber stair. A parapet and crenellated walk with a projecting bartizan (its corbel carved with a human face) crowns the tower in its complete state.

Step inside

8 places to explore in 1400.

The record describes 8 distinct spots at O'Brien's Castle — including 3 interiors: first-floor great hall, mural stairs within the wall, ground-floor vaulted chambers. Create your own photoreal reconstruction and walk through every one — more scenes means more photos, more angles and more rooms of the immersive experience.

Exterior approach from the north ridgeBase of the tower exteriorFirst-floor great hallMural stairs within the wallParapet and battlementsBartizan corbel detailGround-floor vaulted chambersFirst-floor doorway and external wooden stairs

Create History

See O'Brien's Castle with the fires lit.

The artist rebuilds it as it stood in 1400 — a photoreal walk that belongs to you alone. Pay with coins, no subscription needed.

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