Blenheim Palace

I don't know where your coming from to visit the palace but if you have one day, yes, you can see the palace and take the tour along with seeing the beautiful grounds in one day. I went this year and it was stunning!

From London, yes. We did this by rail to Oxford and then S3 bus at the rail station to Blenheim. The bus stop is across the street from the gates.

This might be helpful: https://www.blenheimpalace.com/visit-us/opening-times/

If only visiting Blenheim from London use the train route from Marylebone to Oxford Parkway. This saves time going into and out of Oxford itself.

You can do Blenheim in half a day, some people do Oxford and Blenheim in one day. If you are young and start early, you can do it.

One day would be good, tour the palace, the gardens, the lake, butterfly house and have lunch there. We were there most of a day, and loved it.