Cardiff was a village of under 2,000 people in 1801 and the world's largest coal-exporting port by 1913. Around that boom sit a Roman legionary fortress, a bombed Norman cathedral, Wales' greatest water-defended castle and the dockland streets of Tiger Bay.
Isca Augusta was home to the Second Augustan Legion from AD 75. The museum shows 88 gemstones lost down the fortress bath drain, legionary armour and a reconstructed barrack room. Open 10:00–17:00, free entry.
The only fully excavated Roman amphitheatre in Britain, dug by Mortimer Wheeler in 1926 and known for centuries as King Arthur's Round Table. Seating for 6,000 survives as grass banks; the barrack blocks lie 200m north.
Gilbert de Clare began this 12-hectare water-defended fortress in 1268 to block Llywelyn ap Gruffudd. Its south-east tower has leaned further than Pisa since a Civil War explosion. Cadw site, open 09:30–17:00.
A Norman cathedral on a 6th-century Celtic monastic site, wrecked by a German landmine in January 1941 and rebuilt around Epstein's aluminium Christ in Majesty. Bishop Urban's 1120 arch and the Rossetti triptych survive.
The city's own history inside the 1882 Old Library: how 1,870 villagers in 1801 became the world's biggest coal port by 1913. Objects from Tiger Bay, the 1919 race riots and the Splott steelworks. Open 10:00–16:00.
Sir Ninian Comper's 1928 circular colonnade, with bronze soldier, sailor and airman raising wreaths towards a winged figure of Victory. The Welsh dead of 1914–18 are commemorated in the sunken court below.
World coal prices were fixed on this trading floor from 1888, and the first recorded million-pound cheque was signed here in 1904. Now a hotel, its mahogany-panelled hall and trading balconies stay open to visitors.
The white timber seamen's church of 1868, where Roald Dahl was christened in 1916, moved plank by plank to the barrage side in 1992. Brian Fell's 1994 head-and-hull sculpture nearby honours Cardiff's merchant navy dead.
Over 40 re-erected buildings across 100 acres: the 1762 Rhyd-y-car ironworkers' terrace furnished decade by decade to 1985, a 1948 prefab, a working 1600s farm and the Elizabethan St Fagans Castle. Open 10:00–17:00.
The Gothic mansion built in stages from 1856 by James Harvey Insole on his Cymmer colliery fortune. Left to rot for decades, then rescued by local volunteers; the billiard room, stables and walled garden are open.
By 1900 Cardiff's dockland housed sailors from more than 50 nations — Somali, Yemeni, West Indian, Greek. Loudoun Square, the streets of the 1919 riots and the surviving Bute Street chapels carry that record.
The Terra Nova sailed from Cardiff on 15 June 1910. The 1915 clock-tower lighthouse in the lake carries a model of Scott's ship and a plaque to the polar party; the lake itself is drained Bute marshland, opened 1894.