Fondo d'Oglio Crater and Montagnone Trail

The route

This route links two of the most striking volcanic sites in the Casamicciola Terme area: the Fondo d'Oglio crater, on Monte Rotaro, and the Montagnone hill, which marks the boundary with the municipalities of Ischia and Barano. It starts from the upper part of the Cretaio, reached from Via Cretaio, where a traffic-free clearing overlooks the crater.

From the clearing the trail follows the crater rim and descends to the bottom, now entirely covered by trees. Out of the crater, paths laid out by the Forestry Corps continue east through the woods towards the Montagnone, and from there towards Ischia Porto.

In the version offered in 2025 by the Pro Loco Panza's “Andar per sentieri” series, the hike was given as 4.5 km, about 250 metres of elevation gain and a duration of 4 hours including stops, graded as easy (T, “tourist”). If you continue on foot to Ischia Porto, allow for a longer route.

What you see along the trail

The Fondo d'Oglio crater

Popular sources give a diameter of about 350 metres and a depth of 127 metres. According to INGV's Vesuvius Observatory, the crater was opened by Strombolian activity that partly demolished an older lava dome; the scoria produced by that phase is clearly visible at the crater entrance. On the floor, among holm oaks and chestnuts, grows a hop hornbeam that popular tradition considers an “enchanted” tree.

The fumaroles and the papyrus

Along the route you will come across small fumaroles, emissions of hot steam that recall the activity of the hydrothermal system below ground. Beside them grows the fumarole papyrus (Cyperus polystachyos), a tropical plant that on the island lives only where the steam creates a warm, humid microclimate.

The Montagnone

The Montagnone is a complex of lava domes and pyroclastic deposits: INGV places its first phases in the 6th–5th centuries BC; among the later eruptions, the most recent dated ones go back about 1,400 years. Today it is a farmed hill with vineyards, chestnut groves, holm oak woods and Mediterranean scrub. From the top you can see the port of Ischia with its distinctive circular shape, Procida and the Campanian coast; on the summit stands the iron structure of an old chairlift, now disused, that once carried visitors up from the port area.

How to get there

From Piazza Marina, climb towards the Cretaio via Corso Luigi Manzi, Via Monte della Misericordia and Via Cretaio, all passable by car. Alternatively, walk up from below, entering the Bosco della Maddalena at the Castiglione entrance. The Montagnone can also be reached from the Ischia Porto side, climbing Via Quercia towards Fiaiano.

Useful tips

• Hiking shoes: the descent into the crater has steep stretches on earth and lapilli.
• Water and a snack: there are no drinking fountains or refreshment points in the wood.
• Best time: spring and autumn; in summer, mornings are best.
• Respect the environment: do not leave the paths near the fumaroles and do not pick plants.