Tim Dunn explores disused tube station Down Street in Mayfair that played a crucial tactical role during WWII and tours Rotterdam's new centraal station with the man who designed it.

Tim Dunn visits the Ffestiniog in Wales originally built to transport slate from mountain to coast and learns about Amsterdam Centraal - controversially built across the waterfront.

Tim's behind the scenes at London's King's Cross and learns of Bristol's funicular railway.

Tim Dunn visits the Ribblehead Viaduct in the Yorkshire Dales, talks to the man who saved it from closure and tours the breathtaking stations of the Hungerbergbahn in Innsbruck.

Tim Dunn follows his family's roots by exploring Metroland, the area around the Metropolitan Railway, and in Great Malvern learns about the woman behind the decorative 1860s station.

Tim Dunn explores the ornate St Pancras station in London and its sister hotel - built to show off the might of the Midlands, and learns about Castle Howard station in North Yorkshire.

Tim Dunn rides up Mt Snowdon's railway to visit the summit station, and discovers how a glass structure envelopes Strasbourg's 19th century station.

Tim Dunn visits the former HQ of London Underground, 55 Broadway, which was the capital's first skyscraper, and sees the timber-framed Barmouth Bridge in north Wales.

Tim Dunn visits the architecture of the Stockton & Darlington railway, the first passenger steam line in the world and learns how Essex's enormous Chappel Viaduct was built.

Tim Dunn visits Swindon's railway village, which became home to Great Western's enormous works and he also explores the dark and secret past of Milan's monumental station.

Tim Dunn visits Weymss Bay Station in Inverclyde - an architectural gem. He also explores the engineering marvel that is Blackfriars station in central London.

Tim Dunn visits the Royal Albert Bridge and finds out how it was constructed. He also visits Wolverhampton to learn about the history of its train stations, old and new.

Tim Dunn is in Windsor to find out how two rail companies fought to be first to get to Queen Victoria. He also explores the stunning Connel Bridge in the Scottish Highlands.

Tim Dunn is in London exploring the striking stations of the Piccadilly Line's northern extension. Tim also takes a look at Causey Arch in County Durham.

Tim Dunn rides on a funicular railway powered by water. Also, how an abandoned Victorian railway tunnel in Northamptonshire is being transformed into a racetrack.

Tim explores the last working roundhouse in the UK - Barrow Hill in Derbyshire. Tim also visits Bath, a city renowned for its Georgian architecture.

Tim visits Sheffield station which been reinvented for the 21st century. He also helps to restore the Bennerley Viaduct in the Erewash valley.

Tim Dunn goes behind the scenes at Bristol Temple Meads, a Grade 1 listed station, and is given special access to Brunel's old Tudor station and boardroom.

Tim Dunn explores Huddersfield's Grade I listed station and examines the station's clock, and visits Cologne's magnificent Hohenzollern Bridge in Germany.

Tim Dunn explores Wingfield, one of the oldest surviving railways and uncovers the longest brick viaduct in the UK, the Welland Viaduct in Northamptonshire.

Tim Dunn takes to the tracks in Newcastle, to explore a city rich in railway architecture. He also looks at two recording-breaking structures in Scotland and marvels at the quirky design of a funicular in the German highlands.

Tim Dunn explores Brunel’s first and last railway projects and looks at a Scottish station with a royal connection. Later he takes in the delights of a Portuguese station which looks more like a palace than a railway terminus.

Tim uncovers the secrets above, below and inside London’s Charing Cross Station. He also looks at the modern wonder of the Ordsall Chord in Manchester and tells the tale of two stations in the Swedish town of Boras.

Tim heads underground at the magnificent Bramhope Tunnel and looks at architectural salvage on a grand scale at Fawley Hill. In Germany, Tim finds out how Dresden Station finally rose from the ashes after WW2.

Tim explores Saltburn-by-the-Sea, a town built by the railways, and hears the story of the depot at the centre of Bristol’s tram revolution. Tim also looks at the Polish border station which welcomed Russian Royalty.

Tim visits Bishopstone, a seaside station that’s also a WW2 fortress, and looks at the UK’s first ever high-speed line – the Selby Diversion. He also finds out how the Swedes built a station in a city made up of 14 islands.

Tim explores London’s first passenger railway, the London and Greenwich, and looks at the disused station that was transformed into a huge bookshop. Tim also takes in the record-breaking viaduct in the Czech Republic.

Tim Dunn takes a trip through the history of the North Staffordshire Railway Company, admiring the beautiful Stoke Station.

Tim Dunn heads to the seaside to find out how the railways changed the fortunes of Margate and Ramsgate, and finds out more about 19th-century Dom Luiz Bridge in Porto

Tim Dunn visits the historic Grade 1 Curzon Street Station, to be reborn as part of the terminus for HS2, the rail link between London and Birmingham

Tim heads north of the border to scale a Scottish railway icon – the Forth Bridge, without doubt one of the engineering wonders of the world. Tim conquers his fear of heights to learn its story from its foundations, deep under the Firth of Forth, to its summit 110 metres above the water. At Goathland, North Yorkshire, is a railway station where movie magic was made, possibly better known today as Hogsmeade from its starring role in the Harry Potter films.

In Manchester’s Castlefield area, Tim discovers how viaducts still dominate the cityscape. In Reading, a railway station is transformed and ready for the commuter challenges of the 21st century.

Tim goes deep beneath the waves to explore the Channel Tunnel, stopping off at Ashford International to take in this underappreciated piece of 90s railway architecture. Folkestone Harbour Station, once a great hub for international travel, is leading the way for the regeneration of a whole area of the town.

Tim gets to grips with his local station – London Bridge, meeting the architects who turned this one-time Frankenstein’s monster of a station into the bright, airy and tranquil modern terminus. At the National Railway Museum, Tim gets access to Borough Market Junction Signal Box.

Tim visits the striking post-war Coventry station. In Scarborough he discovers the birthplace of Britain’s funicular railways. And in a TV first, Tim delves into Network Rail’s archives.

Tim explores railway ingenuity at Goole swing bridge in Yorkshire and takes in Edinburgh Waverley from roof to underground vaults. At the National Railway Museum learns how railways demarked their land.

Tim Dunn discovers how two competing Victorian railway companies shaped the city of Lincoln.

Tim Dunn revisits his childhood holiday haunts in South Devon, following the route of Brunel's experimental atmospheric railway.

Tim Dunn explores the birthplace of British locomotive manufacturing - Leeds, starting at the Round Foundry.

Tim Dunn explores beautiful Hull Paragon station and finds out how Royal Leamington Spa got a wonderful art deco station.