The Scilly Islands- New Grimsby Sound

If you are familiar with the Islands and coming from the North,.....

.... New Grimsby Sound would be an ideal initial entrance to the Islands but be aware there is nothing in the way of navigation marks (apart from the lighthouse on Round Island) to assist your entrance and in conditions of wind over tide the seas around the North of the archipelago can be very confused.

If you are just shifting anchorage from the Southern side of the Scillies and want an afternoon's sail then the trip round to New Grimsby is a couple of hours west about or three hours East about around St Martin's; the alternative is to go through one of the Sounds to the east of Tresco. Approaching from the West or NW there are no hazards, the coast is steep to but you may find the sight of the seas crashing against the exposed west side of the islands a little scary; once round Shipman Head at the North end of Bryher just identify Cromwell's Castle and make for that and the anchorage/moorings South of it. If you are coming round from the East, Round Island (with its lighthouse) and the double pinnacle of Men-a-vaur will be easily identified and Shipman Head and the North end of Bryher will slowly open ahead.

Avoid the temptation to head straight for the North end of Tresco from abeam Men-a-vaur, stay north of the transit between Round Island Lighthouse and Men-a-vaur until you can see well into New Grimsby Sound from the NW. This will clear the rocks around Kettle Bottom if they are not already obvious with the seas breaking over them. It's best to veer over to the deeper water on the West side of the Sound until clear of Gimble point before making for the anchorage/moorings.

The approach from St Mary's looks daunting but, in fact, if you make the approach at states of the tide suitable for your draft it is fairly simple (Half tide upwards is best). Remember also that, unlike the waters you may have travelled from, the water here is gin clear you'll see underwater hazards well before they are under your bow.

As you pick your delicate way around the "hazards" you will be embarrassed to be overtaken by the ferries virtually straight lining it from St Mary's to Bryher; don't be, they draw hardly any water and, having been doing it for generations, know where all the rocks are, to the inch!! During your stay at St Mary's you will have identified the lead in marks to the passage clearing Bacon Ledge and the Cow as you leave St Mary's and, once clear of those rocks, can shape a course for Samson Hill on Bryher until you identify Nut rock which you leave well to Port. Pick up the perches on Hulman and Little Rag Ledge. Give the Hulman 30m offing and the Little Rag a good 100m offing. By this time the tide should be well enough advanced for you to head straight across Tresco flats (ignoring the dotted line on the chart) for the gap between Plumb Island and Merrick Island. You should be able to see the Hangman (well into the Sound) as you pass the Little Rag Ledge and if you keep this in line with Merrick island on about 340T until Appletree Point is abaft the beam you'll be well clear of the off-lying rocks there.

Of course if you are deep draft and working the limits of the tide then you should veer round to the West after passing the Little Rag Ledge. Head for the left hand of Samson Hill's two summits until Yellow rock is abaft the beam on about 230T and then turn back NE for Tresco, taking care to clear Lubber's Rock and Plump rocks on the way in. Detailed descriptions of the land marks on this part of the approach can be found in Martin Fishwick's Cruising Companion.

One word of caution here, the tidal streams in the Sound are quite strong (up to 2kts at springs) and change directions four times (as opposed to the normal two) in the tidal cycle. You need to be aware of this when anchoring. It is prohibited to dry out close in to Tresco and you should avoid anchoring so as to interfere with the ferries into and out of New Grimsby Quay. You will be charged for anchoring as well as mooring to a visitors buoy.