Exeter St Davids railway station is the principal and largest railway station in Exeter, also the second-busiest station in Devon.

It is 193 miles 72 chains (193.90 mi; 312.1 km) from the zero point at London Paddington, from where trains travel through Exeter to Plymouth and Penzance. The station is also served by trains from London Waterloo via Salisbury and long distance services to Bristol Temple Meads, Birmingham New Street, Edinburgh Waverley and other places in the North. Local services operate on the Avocet Line to Exmouth, the Riviera Line to Paignton, the Tarka Line to Barnstaple and Dartmoor Line to Okehampton.

It is managed by Great Western Railway and served by trains operated by Great Western Railway, South Western Railway and CrossCountry.

The station was opened on 1 May 1844 by the Bristol and Exeter Railway (B&ER). The station was designed by Isambard Kingdom Brunel and was one of his single-sided stations which meant that the two platforms were both on the eastern side of the line. This side is nearer the city and so very convenient for passengers travelling into Exeter, but did mean that many trains had to cross in front of others.

This was not a significant issue while the station was at the end of the line, but on 30 May 1846 the South Devon Railway (SDR) opened a line westwards towards Plymouth. A carriage shed was built for the SDR at the south end of the B&ER platform but the goods sheds and locomotive sheds for both companies were to the west, between the station and the River Exe. The SDR was designed to be worked by atmospheric power and an engine house was built on the banks of the river near the locomotive shed. This was only used for its original purpose for about a year but was not demolished until many years later.

The next railway to arrive at St Davids was the Exeter and Crediton Railway on 12 May 1851, the junction of which is to the north of the station at Cowley Bridge Junction. This line was worked by the B&ER and trains were accommodated at the existing platforms. All these railways were built to the 7 ft (2,134 mm) broad gauge, but on 1 February 1862, the 4 ft 8+1⁄2 in (1,435 mm) gauge London and South Western Railway (LSWR) brought a line into the station from their own central station in Queen Street. The LSWR owned the Exeter and Crediton Railway and started to work the line for itself, although the broad gauge was retained for the B&ER to work goods trains to Crediton.

With two gauges and four companies using the single-sided station, it was in need of remodelling. A new double-sided platform opened on the western side of the line and the original up platform at the northern end was closed. The original platforms had all been constructed with individual train sheds covering the tracks, and the opportunity was taken to replace these with one large train shed across all the main tracks and platforms. North of the station was a level crossing and just beyond this an additional goods shed was constructed. Unlike the earlier ones, it was solely for transferring goods between the trains of the two different gauges. These buildings were all designed by Francis Fox, the B&ER engineer, and Henry Lloyd and the work was completed in 1864.

The B&ER was amalgamated with the Great Western Railway on 1 January 1876 and the SDR did the same thing exactly one month later. The main line from Bristol was rebuilt with mixed gauge track that allowed broad gauge trains to run through from London Paddington to Penzance, while at the same time offering a standard gauge track for local trains from Bristol Temple Meads; the new line was ready by 1 March 1876.