Fort Frederick occupies the same headland as the Koneswaram Temple, and the juxtaposition of colonial military architecture and ancient Hindu sacred space is one of Trincomalee's defining features. The fort was completed in 1624 — the Portuguese used stone from the temple they had just demolished to build its walls. Today you can walk through the gates freely; the fort is technically still a Sri Lanka Army installation but the historic section is accessible.
The grounds inside the fort walls are home to a population of spotted deer that wander completely at ease among the visitors and military personnel. The contrast of deer grazing next to rusting cannon is one of those scenes that is hard to predict and impossible to forget. The ramparts give good views over the harbour and the bay.