Ticking of WHS is one thing for me but also ticking of countries (I love lists) and with direct flights on KLM from Amsterdam to Trinidad & Tobago I just had to go. Of course also visiting the various TWHS.
How to get to the Pitch Lake
I would say: by car only. On Trinidad public transport is not reliable (except maybe to Maracas beach). Hiring a taxi for a fixed price will do the trick but do count on an easy 100 USD as Trinidad IS expensive! Probably it's better to hire a car for approximate 50 USD / day. You can combine a visit here to the Banwari Site (another TWHS).
The site
It's quite a large area with green around it and in the middle is the Pitch Lake itself. When I visited it was raining quite a lot so it was more a lake of water as that you could see the asphalt and pitch. On the edges you could and the guides even showed the liquid pitch. A visit takes an hour approximate if you do the walk with guide. Do NOT EVER go alone as you can get stuck. It's a dangerous place. At one side they still mine but it's not heavily mined. Interesting is that around the pitch lake there are neighborhoods and even in those places it just pops up everywhere. Also, everything is sinking so building is risky and roads are bumpy.
Should it be WHS?
Yes. It's one of three major Pitch Lake and for sure the biggest on earth. It's unique for sure. I a volcano can be WHS this definitely must be as well.
[photo license for worldheritagesite.org by Els only!]