Harrogate is one.
Mileposts are from Manchester London Road (now Piccadilly) but believe the Down and Up lines are conventionally aligned with regards to London - a rare example of Mileage increasing in the Up direction.
From Marylebone the mileage actually changes several times - Marylebone is measured from Manchester, than at Neasden South Jn it switches to being measured from Northolt Jn then at Northolt Jn it starts increasing away from that point.
Heading towards Aylesbury the Mileage changes at the NR/LU boundary, with the LU (former Met?) mileage continued from Great Missenden (increasing in the down). Just north of Quainton Road the old GC mileage returns, decreasing in the down.
The Princes Risborough-Aylesbury Branch is a different mileage to both lines, making me think it's possibly Zeroed at Paddington. In the same Area, East-West Rail will also be an oddity with the zero just west of Bletchley, so Mileage decreases in the down from Oxford to Bletchley then starts increasing again as it crosses the WCML. I don't know if there's a plan to remile Oxford-Bletchley once EWR opens but I suspect not.
EDIT: Have just found the following old threads which may be of interest
Raising as new thread, from this one on timetables, quoting posts from there, as a separately interesting one The 1850 Bradshaw (reprint unfortunately) has Tables headed 'Down' heading away from London (or any other route) alongside tables headed 'UP' in standard railway convention but the...
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Hi, I'm very new to rail and was wondering how the low mileage end and high mileage end are determined? Is it to do with the Up and the Down, e.g. the UP travels towards higher mileage and the Down towards lower mileage?
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