As of 2011, the UK had over 100 steam railways situated throughout the British Isles and the Isle of Man. That included more than 1,300 working steam locomotives; around 500 miles of track and more than 350 stations. During 2008 these carried over 6 million passengers.

They include both standard- ( 4-foot 8-inch) and narrow-gauge (2-foot) lines. The 20 miles of the West Somerset Railway is Britain's longest standard gauge line. It carries around 200,000 travellers yearly. The Severn Valley Railway -- also standard gauge -- runs 16 miles between Kidderminster and Bridgnorth, attracting 250,000 visitors. Narrow-gauge lines include various Welsh mountain railways, and former mine or quarry railways.

Many steam railways are sections of previously commercial lines, reopened for tourist and educational use. In many cases tracks have been relaid – lines were removed on railway closure in the 1950s and '60s. They are generally volunteer-run by preservation enthusiasts. Some posts – for example driving, administration, civil engineering – may be paid and do require qualifications and experience.

In addition to regular tourist services, steam railways offer special services. These include dinner journeys, Santa specials, Thomas the Tank weekends, school visits; steam galas and steam fairs. Discounts usually apply for group bookings.

Many steam railways offer adults lessons in train driving. Courses vary from half- or full-day introductions to 5-day sessions for advanced skills.