Holy Trinity Church is a Church of South India (CSI) church built in 1834 near the Yercaud lake, making it one of the oldest colonial structures in the Shevaroy Hills. The current building dates from 1853 after damage to the original. It is a simple stone church in the style typical of South Indian hill station churches — plain walls, steep roof, a small tower — and sits in well-maintained grounds.
The church is still in active use and holds Sunday services. The graveyard alongside preserves early colonial-period graves. The setting near the lake and surrounded by old trees is among the most pleasant spots in Yercaud — worth including on any walk around the town.