Hi, we will be on a cruise docking in Dover on Oct. 8, a Tuesday. We will be in port from 8 am until 7 pm. This really means we have from about 830-6 pm. We would like to see Dover Castle and Canterbury either on our own or with a small group tour. Dover castle is open from 10 am-5 pm that day. It looks like we could do this on our own with public transportation, but what would be the best way to do this? But, we are definitively open to a small group tour if anyone has any recommendations. So far, I see mainly day trips to and from London or tours that cover other spots. I did see one tours by locals but it was $1008 dollars (which seems expensive but that was for the group, but it still seemed high), but he was not available on the 8th. Any recommendations for tour companies or the best way to do on our own? Thank you.