A major factor in the development of the town was the coming of the railway. Redhill railway station continues to be an important junction. Redhill is well-known to be one of the few places in the UK where Fuller's Earth can be extracted. Alfred Nobel demonstrated dynamite for the first time at a Redhill quarry in 1867.
A Victorian psychiatric hospital to the south of Redhill, the Royal Earlswood Hospital, was home to two of Queen Elizabeth the Queen Mother's cousins, Katherine Bowes-Lyon and Nerissa Bowes-Lyon for forty years, both of whom had learning difficulties. The inmate James Henry Pullen (1835-1916) was an autistic savant. He was a brilliant craftsman and artist. His work was accepted by Queen Victoria and Prince Albert. Some of Pullen's ship models, designs and art work can be seen on permanent display at the Belfry Shopping Centre, High Street, Redhill. The hospital site has now been converted to luxury apartments.
St John the Evangelist was the first of Redhill's parish churches and the parish originally stretched from Gatton in the north to Sidlow in the south.
On the edge of Redhill is Gatton Park, an estate once owned by the Colmans. The estate had a private chapel (now open to the public) and Japanese gardens that were featured on TV recently. The veteran London to Brighton car rally runs through the town each year.
Over the years the town centre has included many major high street names. It has a market each Thursday and Saturday and sometimes hosts a French market.
The town has a distinctive red-brick theatre-cinema-library complex, called the Warwick Quadrant (housing the Harlequin Theatre and Cinema, library, Sainsbury's and other shops), and an old shopping arcade (that currently houses Road Runners taxi services and among other shops, a small local record store called "Hits" that has been in Redhill since the 1980s). For many years this was simply called "The Arcade"; today its name has changed to "Redhill Indoor Market" although many locals still refer to it by its previous name.
A Sainsbury's store (with underground car park) is situated adjacent to the Harlequin and a parade of modern shops, including MotherCare, Martins Newsagents, Carphone Warehouse & Choice clothing store.
Further along the pedestrianised High Street is the Belfry Shopping Mall which has its own multi-storey car park and over its two floors there are about fifty shops including a post office, recently relocated to inside WHSmith on the lower floor.
In the latter half of 2005, an area full of empty shops and offices was revamped and now includes many eateries such as Frankie & Benny's. This was the first in a series of new developments in the town centre, continuing in 2007 with redevelopment of the neighbouring Kingsgate House site into a landmark office building, and the Lidl/Queensway building into a mixed residential and retail development. There are plans for these to be the start of a wider revamp of the town over the course of the next 10 years, which may take in the Warwick Quadrant, Marketfield Way car park, and Cromwell Road areas.
Local secondary schools include St. Bede's School, which includes a sixth form, and the Warwick School in Noke Drive.
A local night club is currently called 'Liquid and Envy' but is also known to locals by its previous names 'The Embassy' or 'Millionaires' (or simply 'Mares') or 'Busbys', all former names before recent renovation in 2003.
The London to Brighton line is electrified and is operated by trains belonging to the Southern and First Capital Connect operating companies as well as (very occasional) CrossCountry diesel services from Manchester and Birmingham to Gatwick Airport and Brighton. The line splits north of Redhill at Coulsdon and rejoins to the south of Redhill allowing most fast services to bypass Redhill. London-bound trains usually go to either London Victoria or London Bridge. Coming out of London, trains for Redhill usually go on Horsham, Portsmouth Harbour, Three Bridges or Gatwick Airport.
First Capital Connect operates the 'Thameslink' service which goes through London, calling at London Blackfriars, City Thameslink, Farringdon and Kings Cross Thameslink, then continues north to Luton Airport and Bedford. There is a very limited service at Redhill.
The line to the west is electrified as far as Reigate, with some services from London terminating there. Through trains to Dorking, Guildford and Reading are run by First Great Western and are diesel. Trains to stations to Tonbridge to the east, are run by South Eastern. Most diesel services from the North Downs Line go on to Gatwick Airport.
Numerous bus services are operated to the town, by Arriva, Metrobus and Southdown PSV. In May 2008, route 100 to Crawley became part of the Fastway bus rapid transport system, following redevelopment of the town bus station.
Air access is available at Redhill Aerodrome (EGKR) off the A23 1.5Nm south east of Redhill town and at London Gatwick Airport which lies about seven miles to the south on the A23. Heathrow airport is less than an hour's drive to the west and both Luton and London City airports are accessible by train.