Puglia's underground oil mills

Puglia’s underground oil mills

Puglia's underground oil mills

We arrived in the small Puglian town of Presicce on a wet October morning to meet our guide for a tour of the town’s underground olive oil mills. Puglia’s underground oil mills are easy to visit because many towns have them.

The town of Presicce has a huge underground network of these mills: at the height of production in the 18th century, this small town had 23 mills in operation. The reason for all of this concentrated production? The town’s ruler gave tax breaks to anyone who moved to Presicce and set up an oil mill, so entrepreneurs arrived from around Italy.

Some of the mills have been restored and can be visited, so we headed underground with our guide to learn more.

Puglia underground oil mill

Puglia’s underground oil mills made lamp oil

Even today, olive trees cover the Puglia region – the heel of the boot – and produce wonderful olive oil. But the olive oil industry that thrived between the 16th and 19th centuries did not produce olive oil for human consumption. This olive oil was for burning in lamps. Puglian olive oil was fantastic in lamps because it didn’t turn the lamp glass black. This, in turn, saved the person carrying the lamp a lot of scrubbing!

According to our guide, during the 18th century, 26 ships per day departed from the nearby port town of Gallipoli. These ships brought Puglian lamp oil to major cities across Italy and Europe. So what happened in the 19th century to end this booming industry? Electricity happened.

Puglia underground oil mill

Puglia’s underground oil mills: the process

Underground mills cover hundreds of square meters under the historical center of Presicce. The grates on the square (photo above) show where farmers dumped the harvested olives into underground stone holding tanks.

Workers lived underground for the winter months of the harvest season, between about November and May. Workers stayed underground 24/7, working in shifts around the clock: four people worked while four slept. Partly this arrangement was for security: Puglia was constantly under attack. Therefore, the olive oil mills had tight security so the enemy could not access their “green gold”. Even family members who arrived with food had to utter a code word to get access.

After arriving at the underground mill, the olives sat in stone holding areas to ferment. This increased the olives’ acidity to about 18%, which was ideal for lamp oil. (Today, the olive oil we consume ideally has about 1% acidity, which can only happen if olives are pressed right after they are picked. The longer they sit, the higher the acidity.)

To make the oil, workers put the olives on a stone press, which consisted of a horizontal slab sitting under a vertical wheel. A mule attached to the wheel’s wooden axel walked around the press, turning the wheel and crushing the olives into a paste. The photo below was taken at the Gallipoli underground oil mill.

Puglia underground oil mill

Workers transferred the olive paste to coconut baskets, for the second pressing with a different set of presses (photo at the bottom). Water and oil flowed out through the woven baskets into a stone vat, while the olive paste and pits stayed behind. Cleverly, the stone containers that held the oil-and-water concoction had drains at the bottom.  This way, when the oil and water separated naturally, the water at the bottom flowed out of the container. Workers ladled the remaining olive oil into holding containers, ready for transport to the ships.

Puglia's underground oil mills

Puglia’s underground oil mills: fun facts

Puglia's underground oil mills

Puglia’s underground oil mills: planning a visit

If this all sounded great and you’d like to visit, we have a few tips to share. Or, hire us to create your entire Italy itinerary — we’d love to help!

Where: There are many underground oil mills in Puglia, but the most well-known ones are probably in the town of Gallipoli. These are easy to visit as they are open daily, and have a small entry fee. But, they are also the most touristy.

To do the tour in Presicce, contact the tourism office there by email at [email protected]  They do speak English.

Or, to find other oil mills to visit, just do a google search for “frantoio ipogeo” and many will come up.

How Long: We spent about 15 minutes in the Gallipoli underground oil mill, and the Presicce tour was 90 minutes but that also included a visit to the town (recommended!).

How Much: These tours are inexpensive. Entry fees are usually just a couple of euro per person. Even the 90-minute Presicce tour was 5 euro per person (we told them they should increase it!)


Puglia’s underground olive oil mills: Pin it!

Client Testimonials

"We had a wonderful trip! We did so many amazing things and experienced many wonderful places yet never felt like..."

"We thank you so much for all you gave us, guided us to, arranged for, and detailed for us. Not..."

"We are in love with Venice and the Dolomites. The ski adventure was amazing and beyond anything we could have..."

"Absolutely everything that you planned went off without a hitch. Every tour, every restaurant, every train and activity came through..."

"Thank you again from all three of us for your help in planning such a delightful trip. I know that..."

"Madeline carefully planned a fabulous, personalized 19 day itinerary (Lake Garda, Dolomites, N/S Tuscany, Rome) that enabled us to be..."

Read More Client Testimonials

Italy Advice & Tips In Your Inbox

Italy Advice & Tips In Your Inbox

Italy Advice & Tips In Your Inbox

Join our mailing list to get the free Driving In Italy eBook

Your name(Required)

Going Somewhere Other Than Italy?

The Travel Expert Network

Check out the Travel Expert Network where you’ll find Certified Travel Experts™ like us ready to plan custom bucket trips for you all over the world!

Visit the Travel Expert Network →

Office Locations

San Francisco
+1 773 621-3024
Contact San Francisco

+39 320 028 6827
Contact Milan

+39 331 222 2349
Contact Rome

Free Driving In Italy eBook
Start Dreaming About Your Next Italy Trip

Start Dreaming About Your Next Italy Trip

Subscribe to our newsletter.

Your name(Required)