Brno

A modernist house of 1930 whose living room glass wall sinks entirely into the floor. Slots fill weeks ahead, so the booking is made first and the trip built around it.

Work in 2001 opened an underground space holding the remains of some fifty thousand people. Only Paris keeps a larger one in Europe, and the lighting here is kept low.

On the hill above town, with the underground galleries that served as a prison under Austrian rule still open. From the ramparts the city drops away on every side.

Vegetables have been sold on this square since the 1300s, and the stalls still go up each morning. Passages and cellars run beneath it, visited on a separate tour.

A black granite column on the square works as a clock and releases one glass marble at eleven each day. People wait with a hand in each opening hoping to catch it.

A cold war shelter dug for the leadership, with long connecting corridors. It stays cool and damp all year, so a layer is needed.

The twin towered cathedral on the hill rings its bell at eleven rather than at midday. The story goes that during the siege of 1645 the defenders brought noon forward by an hour to hold the besiegers to their word.

Applied art and photography spread across three separate buildings. On Thursday evenings the doors stay open late and entry costs nothing.

A reservoir reachable by tram, busy in summer with pleasure boats and swimmers together. A castle occupies the hill where the water ends, and most people arrive by boat.

Cellars beneath the square were joined into a route passing old wine stores and cells. The ceilings sit low enough that taller visitors duck repeatedly.

A stuffed crocodile known as the Brno Dragon hangs from the entrance passage, beside a wooden cartwheel that legend says took a single day to make. Over the portal, one small pinnacle leans deliberately crooked. The tower climb shows the old town rooftops.

Beneath the Capuchin monastery, friars lie without coffins. Air drawn through underground vents is said to have mummified them naturally. The notorious soldier Baron Trenck rests here too, just off the Cabbage Market.

In Old Brno's Augustinian abbey, Gregor Mendel, later its abbot, grew peas and found the laws of heredity. The museum is inside the abbey, and the foundations of his greenhouse remain in the garden. The Starobrno brewery is next door, worth combining.

Caves in the Moravian Karst north of Brno: you walk in, then a boat on an underground river surfaces at the base of the 138m Macocha Abyss. Summer tickets go fast, so reserve. The caves stay cold even in hot weather, so bring a layer.

Ground where Napoleon beat the Austrian and Russian armies on 2 December 1805, the Battle of the Three Emperors. On the summit of Prace hill stand the Peace Monument to the fallen and a small museum. A re-enactment is held every year in early December.

A Gothic castle stacked in towers and bridges on a forest crag northwest of Brno. Spared major rebuilding for centuries, it keeps a nearly untouched medieval look. From the village, a steep path leads up to the gate.