Cardiff Bay Beyond the Postcard

Cardiff Bay is where the city keeps its superlatives: the world's busiest coal port a century ago, Britain's largest waterfront regeneration after it, and now the seat of Wales' parliament. It is also, fair warning, the part of Cardiff most easily done badly, as a quick photo stop at Mermaid Quay between meals. Done properly, on foot, it is a half day that tells the whole story of modern Wales. Here is the route.

Getting down there

Three good options. The train from Queen Street to Cardiff Bay station takes four minutes and runs frequently. The Princess Katharine water bus runs down the Taff from Bute Park by the castle, around 25 minutes, roughly 8 pounds an adult single, pay on board; it passes the stadium at river level and is the best-value sightseeing in the city. Or walk down Lloyd George Avenue from the centre in about 25 minutes. Arriving by water is the move if the timetable cooperates.

Roald Dahl Plass and the set pieces

Start in the sunken oval plaza named for Roald Dahl, who was born in Llandaff to Norwegian parents and baptised in the Norwegian seamen's church that still stands, relocated, along the waterfront. The plaza is ringed by the Bay's three great buildings. The Wales Millennium Centre's copper-and-slate front carries the bilingual inscription by poet Gwyneth Lewis, six-foot letters that read In These Stones Horizons Sing in English and, in Welsh, Creu Gwir Fel Gwydr O Ffwrnais Awen: creating truth like glass from the furnace of inspiration. The foyer is free to wander and usually has something on. The red-brick Pierhead of 1897, the coal company's old headquarters, is the Victorian survivor. And the Senedd, Wales' parliament, all glass and undulating timber roof, admits visitors free; watching a democracy at work between an opera house and a fudge shop is a very Cardiff experience.

The shrine to Ianto Jones

On the boardwalk at Mermaid Quay, look for a wall of photographs, letters and flowers. This is the shrine to Ianto Jones, a character killed off in the Cardiff-made Doctor Who spin-off Torchwood in 2009, mourned by fans continuously ever since. The Bay was Torchwood's fictional headquarters and remains Doctor Who's real production home, with the BBC's Roath Lock studios visible across the water; Brit Movie Tours runs a guided 90-minute filming-locations walk from the Millennium Centre's entrance if you want the full tour, around 19 pounds an adult, booked ahead. The shrine costs nothing and is somehow both ridiculous and genuinely touching, which many would say is the correct Torchwood register.

Tiger Bay, honestly

Before the barrage, this was Tiger Bay: the docklands of Butetown, one of Britain's oldest multicultural communities, built by sailors and workers from more than fifty nations, the neighbourhood that raised Shirley Bassey. The regeneration replaced derelict docks with the waterfront you are walking, and it also displaced and dispersed much of that community, a tension Cardiff still talks about. The Bay's history boards touch it lightly; the fuller story is worth seeking out, because the glossy waterfront makes more sense, and earns more respect, when you know what it was built over.

The wetlands and the barrage

Walk the waterfront east past the Senedd and the locks come into view. First, the wetlands reserve in the Bay's eastern corner, reed beds built as part of the barrage scheme, where warblers sing within sight of the parliament in spring. Then the main event: the barrage itself, the kilometre-plus embankment completed in 1999 that sealed the Taff and Ely estuaries into a 200-hectare freshwater lake. Walking its top is free, flat and traffic-free, about 3km from Mermaid Quay to the far side, with the still bay on one hand and the Severn Estuary's vast tides on the other; the estuary's range is among the highest in the world, and at low water the exposed sandbanks show exactly what the whole bay looked like before 1999. Cross to the Penarth end and you can climb to that town's Victorian pier and esplanade before turning back.

Timing and appetite

The full loop, set pieces, shrine, wetlands and barrage crossing, fills three to four unhurried hours. Mermaid Quay's restaurants cover the meal; the Millennium Centre's cafe covers the rain. One thing you never need here is a tide table: the water inside the barrage barely moves, which is the entire point of the thing you just walked across.