Story highlights Built in 1949, Azerbaijan's 'Oil Rocks' was the world's first offshore oil well

It is 120km from land but still within the capital Baku's city limits

2,000 people still live and work there every day

The 'city in the sea' has 300km of roads and 256 individual oil wells

"Oil Rocks" is a piece of history. Azerbaijan's "city in the sea" is the site of the world's first offshore oil well.

One hundred and twenty kilometers out into the Caspian Sea, it's still actually within the capital Baku's city limits.

Built in 1949, in Soviet times, Oil Rocks is a huge feat of human engineering. Three hundred kilometers of roads, 256 individual oil wells: this is no small operation.

Two thousand people live and work here every day, working on a one-week shift rotation. Catering to the needs of its citizens, it even has its own museum and restaurants.

Oil Rocks was the world's first attempt to tap into offshore reserves, buried beneath the water. Stalin commissioned the project, before going on to develop Russia's Siberian oil operations.

One drilling platform after another was built and linked up with piers, the foundations formed by sinking ships 1,000 meters to the seabed.

Flying there by helicopter, a thin film of oil over the water is visible -- evidence of the biggest industry in the Caspian Sea region: hydrocarbons. Local oil and gas reserves have been exploited over the years by the Persians, the Ottomans, the Soviets and now Azerbaijan itself.

In Azerbaijan the oil has been flowing for centuries. In 1900, half of the world's production of crude oil came from this corner of the former Soviet Union.

This country is now a transit point for energy exports from the whole Caspian Sea region. Oil Rocks is a fascinating link in the chain of eastern supply and western demand.

Today the site is operated by SOCAR, Azerbaijan's state oil company. A new well was drilled just this month. Over 60 years after it was built and Oil Rocks is still producing oil and gas, still contributing to the Azeri economy.