

Best for beginner divers, 1-140m, shore entry.
Portsmouth Mine is a former iron mine located within the Cuyuna Country Mine Lakes. This freshwater site features artificial reef structures and underwater wall topography. Divers and snorkellers can expect visibility ranging from 10 to 15 metres. The site offers a wide depth range, extending from 1 metre down to 140 metres. Shore access is available, including a swimming beach on the northwest shore that leads to underwater rock shelves. Facilities at the site include parking, toilets, showers, changing rooms, a rinse station, air fills, equipment rental, guided tours, and boat charter services. The site is suitable for beginners, though users should be aware of the significant depth.
46.48950, -93.96480
Avoid flying right after scuba diving.
Located in Crosby, Minnesota. Drive five minutes from downtown Crosby off Highway 30, follow an unpaved road to the campground on the northwest shore for parking, then continue to the swimming beach.
Recorded at this site
Depth
Up to 140m
Visibility
10-15m
Skill Level
Beginner
Entry
Shore
Best Time
May, Jun, Jul, Aug, Sep, Oct
Yes, the site is suitable for beginners, although the extreme depth of the mine requires careful planning and awareness.
The depth at this site ranges from 1 metre to 140 metres.
Access is primarily from the shore, with a swimming beach on the northwest side providing entry to the water.
Yes, snorkelling is a popular activity at this site, which holds a 5/5 snorkel rating.
The site provides parking, toilets, showers, changing rooms, a rinse station, air fills, equipment rental, guided tours, and boat charter services.
Diving at Portsmouth Mine in Crosby requires the following certifications: Open Water. Always dive within your training limits.
The best months to visit Portsmouth Mine in Crosby are May, June, July, August, September, and October. Conditions outside these months can still be good but are less predictable.
Visibility at Portsmouth Mine in Crosby typically ranges from 10 metres to 15 metres. Conditions vary with weather, tides, and seasons.