Short answer: the Abisso Ancona is the headline chamber of the Frasassi Caves, about 200 m high. Sources do not agree on its length and width, and the official site gives no figure, so we do not quote a volume.
What sources say
- Lonely Planet: about 200 m high and 180 m long.
- Wikipedia: about 200 m tall, 180 by 120 m.
- Another source we saw gives 240 by 120 by 80, which does not match either.
When dimensions conflict, the safest wording is “about 200 m high”.
Discovery
The cave system was explored in 1971 by speleologists from Ancona (Wikipedia). Cappanera’s party reached it on 25 September 1971. A farmer had found the entrance in 1948.
Seeing it
You see the great chamber on the standard 75-minute tour, a walk of 1,500 m at a constant 14 C. Tickets are 20 EUR for adults. Stairs are part of the route, so check accessibility notes if anyone in your group has limited mobility.
Allow time to stop and look up: the chamber is about 200 m high.
Want to go deeper? The caving tours use equipment and take 2-3 hours.
Frequently asked questions
How big is the Abisso Ancona?
Most sources say about 200 m high. Lonely Planet gives 200 m by 180 m long, while Wikipedia gives about 180 x 120 m for the floor. Another source gives different numbers, so treat all of them as approximate.
When was it discovered?
Speleologists from Ancona found the cave system in 1971; the leader recorded in Wikipedia is Cappanera, on 25 September 1971. The entrance had been noticed in 1948 by a farmer.
Do you see it on the standard tour?
The standard tour passes through the large chambers. The operator's pages we read give no dimensions.
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