By 1800 the Wandle valley was already heavily industrialised, with about forty factories or mills making textiles, metals, oil, snuff, flour, etc. There was a need for a more efficient way of transporting these goods than the carts on unmade roads which were available at the time.

Thus, the Surrey Iron Railway (SIR) was built from Wandsworth to Croydon by William Jessop - it was probably Britain's first public railway. It was opened on 26th July 1803, had a double 4 ft. 2 ins gauge track, some 13.6 km. (8.5 m.) long (with a 2.4 km.(1.5 m.) branch from Mitcham to Hackbridge) and cost about £7000 to build. It entered Croydon from Mitcham Common, across Waddon Marsh Lane (now Purley Way), along the site of Factory Lane, to Pitlake and Old Town, where a depot was situated near the present Reeves Corner.

The Railway was owned by shareholders - mainly the factory, mill and quarry owners who used the service. Goods only were carried, not passengers, on usually three or four wagons pulled by horses, mules and donkeys up to four miles per hour. Goods transported included limestone, chalk, clay, flints, fuller's earth, manure, cinders, bricks, coal, timber, metals, corn, flour, malt and potatoes. Tolls were charged per ton per mile, depending on what was being carried, and ranged from 1d (less than 0.5p) for dung to 3d (1.25p) for metals and food.

On the 17th May 1803 Royal Assent was given to a Bill entitled: 'An Act for the making and maintaining of a Railway from or near a Place called Pitlake Meadow in the Town of Croydon, to or near to the Town of Reigate, in the County of Surrey, with a collateral Branch from the said Railway at or near a Place called Merstham in the Parish of Merstham, to or near a Place called Godstone Green, all in the County of Surrey.'  This Bill paved the way for the forming of the Croydon, Merstham and Godstone Iron Railway Company (CM&GIR) to which Hylton Jolliffe and his younger brother William belonged.

William Jessop, assisted by his son, was brought in as the Chief Engineer for the CM&GIR. In 1799 William Jessop had been involved in a report and survey on the feasibility of a canal over a similar route as the one covered by the SIR& CM&GIR. His report on the canal stated; 'I went in search of sources from whence might be derived a supply of water, being well aware that strong objections would arise to the taking of water from the streams that fed the River Wandle, the works on which are perhaps more valuable than any others with an equal compass in the Kingdom'' He was unable to find any alternative and further reported; ' 'I am sorry to say that I must consider a canal as impracticable.' So the railway was built instead.

Officially opened in July 1805, much of the CM&GIR was single track although there is evidence that it was doubled at some point in its history. Like the SIR it used Outram flanged plate rails laid on stone sleepers to a gauge of 4ft 2ins with the flange inside. The contractor was Edward Banks who had made his way south building canals and tramways. The track was to run from the Croydon Canal basin (now West Croydon Railway Station) through Old Town, parallel to the Brighton Road down through Purley and Coulsdon then on to the Merstham. From there the line was to have continued on to Godstone Green with a branch to Reigate. The latter parts were never completed, due to construction costs, and the line turned eastward near where the present day Vojan Indian restaurant, formerly the Jolliffe Arms Public House, stands.

From there the CM&GIR was taken only as far as the Merstham chalk and limestone quarries, ending at a house called Quarrydene or Quarry Dean. From this point on, the history of the CM&GIR and the Merstham stone quarries were bound together. This smooth iron road allowed a single horse to pull ten to twenty tons of material from Merstham to Wandsworth, at an easy-paced three to four miles per hour.

There is evidence that George Hall, then manager of Quarry Dean quarries, used both the CM&GIR and the SIR, for at the time he owned thirty-six horses which he used in the transportation of stone from the quarries to Wandsworth, returning with coal. It is also believed that Fullers Earth, quarried locally, was transported using this new railway and sold from wharves at Wandsworth.

Unfortunately the CM&GIR never paid its way and in 1837 it was bought out by the London & Brighton Railway Company (LBRC). In 1846 the Wandsworth to Croydon section was closed and by 1848 both sections were dismantled. William Jessop's skill as an engineer was acknowledged when the new tracks for the LBRC were laid along much of the SIR route and are still used today.

A challenge to the Surrey Iron Railway's claim to be the first public railway to open has been made on behalf of the Carmarthenshire Railway in South Wales which, although authorised later, seems likely to have actually opened shortly earlier.