Wat Preah Inkosei is a small active Buddhist temple in central Siem Reap, notable for its unusual architectural feature: a 10th-century brick tower incorporated into the modern temple compound. The ancient tower is one of the oldest structures in the city itself (as opposed to the Angkor complex outside town), dating from the pre-Angkorian period and built from the same warm red brick as the early Angkor temples. It stands in the modern wat compound, surrounded by newer buildings, the two layers of history in frank juxtaposition.
The surrounding monastery is active and the monks are generally welcoming of respectful visitors. The combination of an ancient brick tower with the bright orange and gold of a modern Cambodian wat is visually striking. It is a five-minute walk from the Old Market and easy to combine with a wander through the surrounding streets.