Oxford to Blenheim

I answered this just the other day.

From the official webpage of Blenheim Palace https://www.blenheimpalace.com/visitus/getting-here/ :

There are three bus routes from Oxford City Centre to Woodstock. All
three services operate every 30 minutes, 7 days a week. Buses stop
outside the main entrance, from where it’s a 10-minute stroll through
the park to the Palace.

Stagecoach Bus S3 and Oxford Bus Company’s 500 run from Oxford train
station. Stagecoach S3 and 7, and Oxford Bus Company 500 all pick up
on Magdalen Street.

Stagecoach Bus 233 operates from Burford via Carterton, Witney and
Hanborough Station to Blenheim entrance. This service operates every
30 minutes Monday to Saturday and hourly on Sundays.

Stagecoach Bus S3 also runs hourly from Chipping Norton to Blenheim.

Note that there is no direct bus service from Bicester to Woodstock.

For bus times and journey planner visit our Good Journey Page or
stagecoachbus.com or oxfordbus.co.uk.

We are offering 30% off Palace, Park & Garden tickets for visitors
arriving by bus on our website, use the code GREEN30 at our online
checkout.

From the Railway Station the journey takes exactly 40 minutes on the 500, 8 minutes shorter from the centre of Oxford.

My preference would be the 500 which runs every half hour... https://www.oxfordbus.co.uk/services/OXBC/500?date=2021-11-16&direction=outbound

We asked our hotel for car service options and hired a car to deliver us and pick us up a few hours later. This was in 2013 so I don’t remember any other details. If you are going at night, do yourself a favor and hire a car. You might check Uber or Lyft too.

There is a big shake up of Oxfordshire bus routes taking effect from 2 January to reduce overlaps. This will eliminate the Oxford Bus Company 500 route but the Stagecoach 7 will be changed to compensate.