Port St Mary (Port Code:GBPSM) is a classic small harbour in a beautiful setting. It is popular with diving clubs with organised trips to dive sites. Fishing excursions also leave from Port St Mary during the tourist season. The harbour is used by fishing vessels, pleasure craft, occasional commercial coasters and passenger vessels. Port St Mary consists of an inner drying harbour and an outer always afloat berthing harbour.
Berths are varied with both tidal and deep water facilities. Four white topped Visitors buoys (seasonal) northwest of the Alfred Pier Head. Good protection except in strong S and SE winds. Depth of at least 4M. The use of a chain preventor is strongly advised. Chapel Bay with depths between 3M and 6M. Craft up to 11M and less than 2.5M draft moor in the inner end at ladders 1 to 4. There may be a need for craft to tie up alongside other craft and the use of fendering and shore lines is essential. Craft in excess of these dimensions, or craft not suitable to raft alongside other craft should moor at the visitor mooring buoys or anchor. The inner harbour with ladders 8 to 12 are those normally used by visiting craft. There are 2 full tide and one half tide slipways.