Italy
An underground void so vast Milan's Duomo would fit inside, stalactites still growing in darkness.
The temperature drops as you descend, and then the first chamber opens. Your eyes chase the ceiling and lose it; the void outruns the lights. Stalactites hang in clusters like frozen chandeliers above a silence measured in dripping water.
The Frasassi caves under the Marche hills were found in 1971, when cavers from Ancona dropped into a sinkhole and became the first humans inside. The Abisso Ancona, the vastest chamber, runs roughly 180 metres long and up to 200 high, a space big enough to hold Milan's cathedral. The show route threads some 1,500 metres of lit formations at a constant 14 degrees, identical in January and August, while a booked adventure route takes overalls and helmets into the unlit sections. Above ground, the Gola della Rossa gorge and its regional park hold peregrines, monasteries and river walks.
Family
The first chamber makes children and adults gasp on the same beat, and the lit route asks nothing hard of anyone.
Friends
Book the caving route: overalls, helmets and wriggling into chambers day visitors never see, with crescia and salami earned afterwards.
Crescia, a lard-enriched griddled flatbread, folds around ciauscolo, the Marche's spreadable salami.
Verdicchio dei Castelli di Jesi brings a mineral edge that suits a day spent underground.

Tottori Sand Dunes
Japan
Wind-rippled dunes rise above the Sea of Japan, with camel rides across the sand.

Nullarbor Plain
Australia
A treeless plain ending in sheer cliffs that drop into the Southern Ocean to the horizon.

McCluskieganj
India
A crumbling utopian Anglo-Indian settlement being slowly swallowed by the dense forests of Jharkhand.

Cascate delle Marmore
Italy
Romans sent a river over a cliff in 271 BC; the thunder still obeys a timetable.

Etna
Italy
Europe's tallest active volcano, lava fields, sulphur vents, and vineyards growing in volcanic ash.

Orrido di Bellano
Italy
Catwalks bolted to the rock carry you through a slot gorge with water roaring beneath.

Ponza
Italy
A volcanic island off the Lazio coast where Romans cut eel pools into the sea cliffs.