I will be with a friend in September in Canterbury. We are considering a day trip to Calais rather than a night in London. (We have both spent some time in London on prior trips). Wondering if this is worthwhile or if we are better off going to London. We will have just spent 4 days in Canterbury.
If we spend the night in London we will probably take in a show. Our flight leaves the next day from Heathrow. (Late afternoon).