
A two-and-a-half kilometre boulevard with Europe’s oldest continental underground running beneath it — and the walk is free.
What it costs
Free to walk, and walking it is the recommendation: it runs from the centre out to Heroes’ Square, getting grander and quieter as it goes.
What is ticketed is what stands on it — the Opera House, the House of Terror museum, and the villas at the far end. The M1 metro beneath it runs on an ordinary transport ticket.

When to go
Any time. Autumn is the season here — the whole length is planted with trees, and the outer half is residential enough to be genuinely quiet.
Getting there
Metro M1 runs the whole length with frequent stops, so you can walk as much as you feel like and ride the rest. That is how the line is best used.

If you only have an hour
Ride the M1 out to Heroes’ Square and walk back down. Downhill in feel if not in fact, and the avenue reveals itself in the right order — villas, then apartment palaces, then the Opera, then the centre.
What people get wrong
The M1 is often called the oldest underground in Europe. The defensible version: it opened in 1896 and is the oldest electrified underground on the European continent — London’s is older, and predates electrification. The avenue and the line beneath it are UNESCO-listed together.

Nearby
Ticketing arrangements and opening patterns as published for 2026 and checked on 4 September 2026. These change without much warning — confirm with the site itself before you travel. More sights, and how they fit together, in Landmarks & Sights.