Tunapuna–Piarco is the fifth largest region in Trinidad and Tobago accounting for an area of 527.23 square kilometres (200 sq mi). The region has approximately 30 km (19 miles) of rugged coastline with the Caribbean Sea to the north.

Tunapuna–Piarco is one of the most geographically diverse regions in Trinidad and Tobago. It features the country's two highest mountain peaks, El Cerro del Aripo at 3,084 feet and El Tucuche standing at a soaring 3,070 feet, which both tower the north of the region and the Northern Coast of Trinidad forming the a part of the Northern Range.