Darlington had two bay platforms for Bishop Auckland till the '80s. Access was before the main station.
Northallerton had several including a low level station for a short period. Never sure how the mainline ones were as the station is now on a fairly narrow embankment.
Northallerton High Level had 6 platforms. There was a south facing bay to the east of the current up platform and is still in situ without track but fenced off. The current down platform was part of an island platform and part of he outer face is still in situ fenced off but the northern end has been removed, together with the two north facing Hawes bay platforms within the island, for car parking. The outer face and south facing bay were decommissioned with the closure of the Ripon line in 1967.
Harrogate used to have 9 platforms now only two with an out of use east facing bay used for stabling units overnight. Again most decommissioned after closure of the Wetherby line in 1964 and Ripon line in 1967.
Lydney Junction had 5 platforms until the line across the Severn Bridge to Sharpness was severed in November 1960 reduced it to 3. The rarely used up bay platform was decommissioned sometime in the 1960s and track removed when Westbury-on-Severn, Newnham and Awre stations closed. Grange Court Junction also lost two platforms on the main line at this time but retained two on the Hereford branch until closure in 1965 together with Oakle Street station.
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Bridlington used to have 8 platforms, two through platforms and a bay 1-3 on the west side and two through platforms, 4&5 and three excursion bay platforms 6,7,8 on the east side. 1-3 were taken out of use about 1980 and short-sightedly sold for housing. Excursion platforms 7&8 were decommissioned at about the same time but still present and derelict in 2007 leaving only three platforms 4,5,6.