The North Sound is on the Northern end of Virgin Gorda and is a large bay that is well protected by Virgin Gorda as well as the surrounding Islands and reefs. The North Sound is one of the highlight destinations in the BVI as it has a wide variety of anchorages, great beaches, things to do for everyone and it can serve as the jumping off point for a visit to Anegada. The North Sound is definitely a place you can spend a couple of days.
There are two entrances to The North Sound. The Colquhoun Reef Entrance and the Anguilla Point Entrance.
If you are chartering, there is really only one way into the North Sound that is recommended, that is approaching from the north and running between Mosquito Island (which you will leave to starboard) and Prickly Pear Island which you will leave to port.
If you are coming from the Sir Francis Drake Channel you will be heading East with Mosquito Island off of your starboard side. As you approach the channel leading into the North Sound, you will see Mosquito Rock prominently off the north eastern end of Mosquito Island. While there is good water near the rock, be sure to leave plenty of room as you turn to enter the sound, just behind the rock as you enter is Colquhoun Reef which is very shallow and should be given a wide berth.
You will pick up the entrance buoys just off Cactus Point on Prickly Pear Island. There is also a reef that extends off of Cactus Point so passing thru this set of buoys is important. There is a green flashing buoy that you will leave to starboard and a red flashing buoy that you'll leave to port.
There will be two green buoys marking the port side of the channel and three red buoys marking the starboard side of the channel. Split these buoys and your entrance will be easy.
If you are heading to Drake's Anchorage which is along the eastern side of Mosquito Island and on the Western side of Colquhoun Reef, make sure that you round that third red buoy leaving it to your starboard. There is shallow water if you cut it and you will risk running aground.
Likewise, if you are headed to Leverick Bay or Gun Creek, these will be on your starboard side and be sure to leave that third red buoy to starboard as well.
If you are looking to go to Biras Creek, The Bitter End or Saba Rock, you will simply proceed along Prickly Pear and around Vixen Point. Leave room off Vixen Point and you will have Saba Rock to your immediate port side, The Bitter End will be on your port side and Biras Creek will be just ahead on your port side. Once around Vixen Point, there is good water as evidenced by the spectacular mega yachts that frequent the North Sound. However, the only obstruction to be aware of Oyster Rock at the Eastern end of the sound towards Biras Creek. It is marked with a red buoy.
If you are chartering or are unfamiliar with the area, you are best to avoid entering North Sound via the Anquilla Point entrance. It looks like a nifty shortcut as you head up the Sir Francis Drake (you can see the Bitter End cottages!) and it does in fact have ~6 feet of water but it is definitely a more risky approach. Many bareboat charter companies advise against or prohibit use of this entrance. Resist the temptation and enjoy the longer sail!