As a transit-loving kid who turned into a transit-loving adult, I can fully relate to your child's obsession – even now, I'm thrilled if I snag the front seat on a Vancouver SkyTrain.
While I've hopped on Zurich's bustling blue trams, Japan's sleek shinkansens (the bullet train) and the Formica-lined East German carriages of the Trans-Siberian Railway, I'd recommend San Francisco for your wide-eyed tyke.
It's crammed with fun transportation experiences – and plenty of diversions for parents who don't know the names of every Thomas the Tank Engine character.
"You've made the right choice if you come here," says Rick Laubscher, chair and president of Market Street Railway (streetcar.org), the organization that preserves the city's historic transit lines and runs the San Francisco Railway Museum. He recommends three essential rides.
"First, one of the historic streetcars that run on the F-Market and Wharves line, so they can feel what transit was like more than 50 years ago. Second, a ride on an old cable car to experience transit from 125 years ago. Third, the sleek trains of Bay Area Rapid Transit [BART] to see what is still one of America's most advanced regional mass-transit systems."
The first option is my favourite. Highlights of the bone-shaking collection of restored streetcars from the U.S. and beyond include streamlined cars from Milan and 1930s England.
San Francisco's iconic red cable cars are also a must, but avoid lengthy queues by making it your first experience of the day. Get onboard at the waterfront Hyde and Beach turntable stop, then enjoy a breathtaking roller coaster hill ride toward Union Square. Stop en route at the Cable Car Museum to watch the whizzing under-road steel lines that drive the system.
Laubscher adds that his organization's website will soon post 2013 special events for transit fans – one of the cable car lines marks its 125th anniversary this year, for example. For longer stays in the region, he recommends Sacramento's California State Railroad Museum and the Western Railway Museum near Fairfield.
Closer to home, Canada is teeming with kid-friendly transit museums and historic rides. Among the best is B.C.'s West Coast Railway Heritage Park in Squamish. It has dozens of antique trains on display and regularly schedules family activities (book ahead for spring break's Dinosaur Train).
But if buses top your kid's wish list, it has to be London. Aside from its mainline trains and clamorous Underground (check ahead for 2013's 150th anniversary events), vintage Routemaster double-deckers still trundle along two "heritage routes" – the most popular between Tower Hill and Trafalgar Square. You can peruse older examples at Covent Garden's London Transport Museum.
Make your trip special by aiming for one of the museum's open weekends at its Acton Depot storage facility. With a vast collection of mothballed trains, buses and more, these events are crammed with family-friendly activities and smile-triggering vehicle rides.
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