Classroom lesson · Pitch Lake · 🇹🇹 Trinidad and Tobago

Pitch Lake

The world's largest natural asphalt lake

Photo · Wikimedia Commons

What is it?

Pitch Lake in Trinidad is the largest natural lake of asphalt in the whole world. Instead of water, it is filled with thick, black, sticky asphalt that slowly bubbles up from deep underground. The lake covers about 40 hectares — that is bigger than 50 football pitches!

Tell me more

Asphalt is the same material used to pave roads and runways. At Pitch Lake, it has been oozing naturally out of the earth for thousands of years. The surface looks dark and solid, but if you stand still for too long in the same spot, you slowly start to sink — so visitors keep moving!

Scientists have found tiny living things called microbes deep inside the asphalt. These microbes survive without sunlight or oxygen, which is very unusual. Studying them helps researchers understand how life might survive in unusual places elsewhere in our solar system.

People have been collecting asphalt from this lake for a very long time, and yet it keeps refilling itself. Experts think there is a huge underground reservoir pushing the asphalt up from below, a bit like squeezing toothpaste from a tube that never runs out.

Pitch Lake is one of Trinidad's most famous landmarks. Tour guides walk visitors across the surface and show them spots where warm, clear water bubbles up through the asphalt — making strange little pools right in the middle of the black lake.

In the classroom

Walk your class through this in 15 minutes.

Talk together

Discussion prompts

  1. 01How is Pitch Lake different from any other lake you have seen or heard about?
  2. 02Why do you think scientists are excited about tiny creatures that can live in asphalt without sunlight?
  3. 03Asphalt is used to build roads. Does knowing it comes from a natural lake surprise you? Why?
  4. 04If you were a tour guide at Pitch Lake, what three things would you tell visitors first?
Try this

Classroom activity

Draw a cross-section of Pitch Lake showing the surface, the asphalt layer, and the underground reservoir below. Add labels, arrows showing the asphalt moving upward, and one tiny microbe with a speech bubble saying something it might 'think' about living underground.