Over the following 17 years the line steadily extended into the Hawkes Bay interior, and on 9 March 1891 it opened through the Manawatū Gorge to Palmerston North.
The Napier Express commenced just after the railway opened to Palmerston North in 1891 and ran once each way daily, typically hauled by a J class steam locomotive.
In 1909 the Napier Express was diverted from the Wairarapa Line, through the Manawatū Gorge to Palmerston North, and then to Wellington over the former WMR track.
On 20 February 1911 when the express was approaching Paekākāriki from the south, a large boulder dislodged from above on the Paekakariki Escarpment rolled down onto a second class carriage, killing Miss Alice Power (23y) from Greymouth who was travelling with two friends.
[1][2][3] By 1914 the travel time was 9 hours 4 minutes with track improvements in 1914 which allowed the speed limit in some places to be raised to 73 km/h and the more powerful A class locomotives was introduced about 1917-18.
In 1954, due to a severe shortage of crews, and coal, the Express was withdrawn just days before Christmas, and replaced by an RM class Standard railcar service.