From the Rockport area, the remainder of the cruise through the Thousand Islands is relatively uneventful from a navigation standpoint. The shipping channel is well marked, and there are few other routes to follow safely.
From the Sutherland Group to Brockville the river is dotted with numerous islands and many unmarked shoals. If you leave the channel, be careful where you go. While there is safe water and locals know how to navigate through this area, there are also many shoals lying in wait for your running gear.
Both the southwest and the northeast portions of Grenadier Island, which is on your port side,and Adelaide Island,off the northeast point of Grenadier, belong to St. Lawrence Islands National Park.There are docks accessible on these islands.
As you reach Brockville and the Brockville Narrows, you are leaving the Thousand Islands.
Currents through the Brockville Narrows can have an affect on handling, and the surge from passing ships can cause dangerous conditions,especially close to shores.
The city of Brockville owns a number of islands along the narrows that have docking facilities,and there is a great deal of small craft activity here in the summer. Some of these islands permit overnight docking and some do not. Fees are collected by the island superintendent.
The first island and docks accessible on arrival are found on the northwest end of Sheaffe or Black Charlie Island. You may turn to starboard past Myers Island and approach the docks straight in.There are three small docks that are typical of the Brock Group.
Proceeding west along the south shore of de Rottenberg Island,you will find several small docks best suited for use by runabouts and small pocket cruisers.
To explore the rest of the islands in the Brock Group it is best to stay in the marked channel on the south side of the islands. While the channel is marked, unless you are familiar with the area it is still best to post a bow watch.