This is going to be a long description, maybe you should sit down, grab a Coke. But first, a quote from Stuart (Peter Sam) and Falcon (Sir Handel)!

"Engines come and engines go, but Granpuff 'goes on' forever!"

I won't put in anything about Duke because this is already long enough.
Info from the Thomas the Tank Engine Wiki

Prince is (probably) the third of the first four locomotives. He is now numbered No.2, but there is doubt about the order of building and numbering of the first four England engines. He was delivered to the FR in January 1864. These locomotives were worked hard; before the arrival of Taliesin, they were coming in for a 2 week period of maintenance every quarter. In this period they would replace brake blocks, brasses and cotter pins in the crank pins as well as replacing some of the firebars. In 1878 Prince had his chimney knocked off and that of Mountaineer was put on. By May 1881, Prince was in a poor state with his boiler pressure restricted to 110lbs. He had a major refit with a 'sham' cast iron tank fitted on top of his side tanks to increase the weight to ten tons and improve adhesion in wet weather, a new weather board, new sandboxes, new cylinders, and his boiler re-tubed. However the boiler was wearing out and he was withdrawn on 16th May 1891.

In 1892, the original arrangement was replaced with the present full cab and saddle tank. At the same time the name The Prince was shortened to just Prince. In 1894 he broke the front axle and an old one from Little Wonder was used as a replacement. The England engines continued to be the workhorses of the line and Prince was re-tubed in 1898 & 1901. In 1912 he was fitted with Welsh Pony’s smokebox. He continued in service until 1915, then lay out of use until a new boiler was fitted in 1920.

The locomotive played a major role in the history of the Welsh Highland Railway, hauling the first train from Dinas to Porthmadog in 1923, and regularly performing on both lines in the 1920s and 1930s. In 1932 he had an overhaul which repaired the smokebox and tank. However time was running out for the boiler and Prince was withdrawn around 1936. A new boiler was ordered in September 1943 originally for £546, but the actual cost became £640 when delivered in July 1945.

In 1954, his new owners found him as he was left in 1946: in mid overhaul and with a new boiler. He was the obvious candidate for first loco to be restored. He first ran in preservation on August 2nd 1955 and was the mainstay of the service for the next 2 years. By 1962 Prince was in need of a major overhaul and was given a different frame arrangement, to try and take the drawbar load through the frames and not the boiler. This was the form in which he ran for his Centenary in 1963.

Withdrawn in 1968, the locomotive was considerably rebuilt between 1974 and 1980 with the 1955 boiler superheated, oil firing fitted, new outer frames added to carry the cab (raised by 4"), and saddle tank.

On the left side of Prince's tender are four bushes, apparently indicating that the metal sheeting once carried a locomotive nameplate. Measurement of the bushes indicates that the tender side sheet possibly originated as part of one of Taliesin’s original side tanks. When converted to oil-firing, Prince was provided with oil and water tanks in the tender.

In 1986 Prince was chosen to be the first FR engine to be put in an historic livery. The red livery was chosen because of the 1920s livery found during the 1980 rebuild. In 1987, Prince's frames started to break. Strengthening plates were put in that winter and the loco was able to celebrate his 125th anniversary in 1988 in good order again.

In 1995 a brass handrail was restored to the smokebox and in winter 1995/6 the water tanks were removed and a new, less obtrusive oil tank inserted. Prince had an overhaul between 1997 & 1999 during which the boiler was re-tubed, the chassis was given a thorough overhaul, and further cosmetic improvements were made. The loco re-emerged with the same red livery, but with improved lining.

Prince has travelled far during the preservation era, visiting Olympia in 1984, Chatsworth House in 1987, York for the Railfest Exhibition in 2004, Three Superpowers, one Vintage Weekend and one Beer Festival on the WHR(C). In September 2008 he attended the Garratt 50 Gala on the WHR(C). Prince Charles drove Prince on the opening of the WHR to Rhyd Ddu in 2003 - Prince being the only locomotive that could be used with the track as originally laid. Unwittingly, this echoed the locomotive's role in the opening of the WHR in 1923 when, as noted above, Prince pulled the first train from Dinas to Portmadoc.

On 23rd March 2007 Prince took part in the opening of the WHR(P) extension from Pen-y-Mount to Traeth Mawr loop.

On 27th October 2007 Prince & Palmerston became the first England Engine to go to Cwm Cloch in over 71 years, for a photographic special.

On 24th October 2008 Prince and Palmerston became the first England engines to pass through the Aberglaslyn Pass in 72 years for a photographic special.

On 21 May 2009 Prince broke the banner at Beddgelert Station, to declare the route through the Aberglaslyn Pass open. Later that day he hauled the first fare-paying passenger train through the pass.

Prince is currently out of service as his boiler certificate expired in May 2010. He went to the Severn Valley Railway to be on display in the Engine House in Highley. In Summer 2012, Prince returned to Boston Lodge for his overhaul.

In April 2013, Prince went to Acton Works in London, to give rides during the Easter Holidays.

Prince participated in the Talyllyn Railway's 150th celebration with Russell from July 3rd to July 5th, 2015.

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