Both the northern and southern entrances to Nanaimo harbour are busy seaplane landing areas are not places to hang around in whilst you get your sails down.
There are several commercial marinas in the northern end of Newcastle Island Passage but these seem to have only limited space for visiting yachts.
The Nanaimo Yacht Club Marina which lies at the southern end of the Passage offers reciprocal berthing facilities on its K and L pontoons which are the 2 southernmost in the marina. No reservations are accepted and berths are only available on a first come first served basis. If there is a space available simply tie up and register at the office. The club Marina does not monitor VHF. The berths are very popular and if you arrive late in the day during the summer you are unlikely to find space.
The Waggoners Pilot says anchoring is now prohibited in Mark Bay. This appears to be only partially true. The innermost part of the bay is filled with visitors moorings, but anchoring is still permitted in the outer part of Mark Bay provided you stay north of the special buoys which mark the seaplane landing area. Exceptional holding in 8-10m, sticky mud. The anchorage is very popular and by mid afternoon may be full. A NW wind seems to funnel through the anchorage which is not quite as calm as one might expect under these conditions.