Grotte de Lorette, Rochefort

The Grotte de Lorette lies directly beneath Rochefort and was discovered in 1865, and its distinguishing feature is the Sabbath Hall, a chamber some sixty metres high whose roof cannot be lit from the floor, so the guides send up a small hot-air balloon to show the scale, which is the thing every visitor remembers. The route descends about sixty-five metres through galleries with formations, a chasm crossed on a footbridge, and chambers whose acoustics the guides use. It is smaller and less grand than Han-sur-Lesse a few kilometres away and correspondingly less crowded, and it is reached on foot from the town rather than by tram. The temperature underground is a constant nine degrees.

What you actually see

• The Sabbath Hall - a sixty-metre chamber measured by a balloon sent up.
• The chasm footbridge - a crossing over the drop inside the cave.
• Formations along the galleries - stalactites and flowstone on the route.
• A constant nine degrees - the underground temperature year round.

When to go

April to October; it closes or runs limited tours in winter. Two hours including the walk from town. Tours run at set times. Bring a jacket regardless of the weather above ground.

Honest expectations

It is much smaller than Han-sur-Lesse and visitors who do both are usually more impressed by Han. Tours are timed and in French unless arranged. There are many steps. The balloon is a piece of showmanship, which is either charming or silly.

Nearby

Han-sur-Lesse caves are a short drive; Lavaux-Sainte-Anne lies west.