# Grotta Gigante: one hall 98.5 m high, 1,000 steps

> The Grotta Gigante at Sgonico is one hall 98.5 m high: 500 steps down and 500 up at 11°C, €15. The Opicina tram has been running again since July 2026.

URL: https://myitalia.it/attractions/grotta-gigante-e-carso
Last updated: 2026-09-11

The Grotta Gigante, at Sgonico on the Karst plateau outside Trieste, is a single cave hall 98.5 meters high, 167.6 long and 76.3 wide, visited on 500 steps down and 500 back up at a constant 52°F (11°C), for €15.

## One hall, 98.5 by 167.6 by 76.3 meters

The cave is one chamber, 98.5 meters high, 167.6 meters long and 76.3 meters wide, and it has been in Guinness World Records since 1995 as the largest natural hall in the world open to tourists.

The hall also holds the longest geodetic pendulums in the world, run by the University of Trieste, which makes it a working research site as well as a show cave.

One caveat on the numbers: the dimensions and the record come from an encyclopedic source, because the operator's open pages don't display them. The prices, the steps and the temperature below are the operator's.

## 500 steps down, 500 up, at 11°C

The tourist route is 850 meters long and goes down 101 meters, on 500 steps into the hall and 500 back out. It takes about an hour, at a constant 11°C, which is 52°F in any month.

That is the physical fact to plan around. A thousand steps in an hour is a workout for knees, and the second 500 are all uphill. Bring a layer even in August, and shoes with grip.

Booking is required. The operator's timetable of departures is not in our records, so check it when you book.

## €15, €12, €8, and the FVG Card

The full ticket is €15, reduced €12, ages 6 to 18 pay €8, and children up to 5 go free. Groups of 15 pay €12 each and school groups €6.

The FVG Card, the regional visitor card, gives free entry together with one child under 12. If you're touring Friuli with a family, that single line can be worth more than the card's other benefits.

## The Opicina tram, back since July 27, 2026

Line 2, the Opicina tram, climbs 5.175 kilometers from central Trieste onto the Karst, and about 800 meters of that is pushed by a funicular up gradients of 26%, a system with no equal in Europe.

It resumed on July 27, 2026, with a provisional terminus in Piazza Dalmazia. The historic terminus in Piazza Oberdan is due for works from late 2026 to June 2027.

Its recent record explains the caution. The line stopped after an accident on August 16, 2016, came back on February 1, 2025, stopped again on October 12, 2025 with a cable fault, and returned in July 2026. The official transport page had not recorded the 2025 stoppage when checked, so the return comes from a news agency.

On board, loads are capped at 80% of capacity and standing is allowed only on the rear platform. It is not accessible to wheelchair users. Urban Trieste tickets are valid, and you can pay contactless on board.

The tram takes you onto the Karst. The last stretch from the line to the cave at Sgonico is not covered in our records. The city below is at [Trieste](/towns/trieste), and why its history runs differently from the rest of Italy at [Trieste was not Italian](/stories/trieste-was-not-italian).

## FAQ

### How many steps are in the Grotta Gigante?

1,000: 500 down into the hall and 500 back up, on a tourist route of 850 meters that reaches 101 meters below the entrance. The visit takes about an hour at a constant 11°C (52°F), so bring a layer and shoes with grip.

### How much is the Grotta Gigante?

€15 full, €12 reduced, €8 for ages 6 to 18 and free up to age 5. Groups of 15 pay €12 each and school groups €6. The FVG Card gives free entry with one child under 12. Booking is required.

### Is the Opicina tram running?

It resumed service on July 27, 2026, with a provisional terminus in Piazza Dalmazia, after a cable fault stopped it on October 12, 2025. The line has been unstable since a 2016 accident, so check its status on the day before relying on it.

### How big is the Grotta Gigante?

A single hall 98.5 meters high, 167.6 long and 76.3 wide, in Guinness World Records since 1995 as the largest natural hall open to tourists. Those dimensions come from an encyclopedic source, because the operator's open pages don't display them.

## Sources

| Fact | Source | Confidence | Valid until |
|---|---|---|---|
| La Grotta Gigante, sul Carso a Sgonico, contiene una sala unica alta 98,5 metri, lunga 167,6 e larga 76,3, dal 1995 nel Guinness dei primati come la piu' grande sala naturale al mondo aperta ai turisti: si percorrono cinquecento gradini in discesa e cinquecento in salita a 11 gradi costanti, biglietto intero 15 euro | [Grotta Gigante](https://www.grottagigante.it/en/price-list/); [doc 2](https://www.grottagigante.it/en/home/); [Wikipedia](https://it.wikipedia.org/wiki/Grotta_Gigante) | medium | 2027-06-30 |
| Il tram di Opicina, linea 2, sale dal centro di Trieste al Carso su 5,175 chilometri e comprende un tratto di circa 800 metri spinto da una funicolare con pendenze fino al 26%, caso unico in Europa; fermo dall'incidente del 2016, e' stato riattivato il 1 febbraio 2025, si e' fermato di nuovo il 12 ottobre 2025 per un guasto alla fune e ha ripreso il servizio il 27 luglio 2026 con capolinea provvisorio in piazza Dalmazia | [TPL FVG](https://tplfvg.it/it/servizi/tramopicina/); [ANSA, 18 luglio 2026](https://www.ansa.it/friuliveneziagiulia/notizie/2026/07/18/riprende-il-servizio-dello-storico-tram-trieste-opicina_d2626a04-22a2-43d0-b8ae-fff87f7f3a73.html) | medium | 2027-06-30 |

## Image

https://media.myitalia.it/media/city.trieste.1600.jpg
Author: Diego Delso. License: CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0).
Source: https://commons.wikimedia.org/wiki/File:Ayuntamiento,_Trieste,_Italia,_2017-04-15,_DD_10.jpg

## Other languages

- it: https://myitalia.it/it/attrazioni/grotta-gigante-e-carso.md
- es: https://myitalia.it/es/atracciones/grotta-gigante-e-carso.md
- fr: https://myitalia.it/fr/attractions/grotta-gigante-e-carso.md
- de: https://myitalia.it/de/sehenswuerdigkeiten/grotta-gigante-e-carso.md