On the shore at Lower Upnor are two London stones. These stones mark the boundary of the charter rights of the fishermen of London to fish round into the Medway, on the northern side only.

The bigger, newer of the two stones is in brown-grey granite, it records visits from London dignitaries.

The smaller stone is the older one, on the side facing away from the river it has enscribed "God preserve the City of London". On the river facing side it has the year 1204 and the arms of the City. Below that are the names of eighteenth century civic dignitaries of the capital, recording their ceremonial visits to the stone. The other two sides of the stone also records visits, but are now almost indecipherable.