The cold layer
Karst springs push cold fresh water into the Bay of Kotor, including from the seabed. The result is a halocline and thermocline — a visible, shimmering boundary where fresh meets salt, often between five and fifteen metres, with a sharp temperature drop through it.
In August you can have 26 degrees at the surface and 16 below the layer. Divers who planned a shortie on the basis of the surface temperature come up cold. A 5 mm suit is the sensible default in the bay all season.
Visibility by month
| Bay of Kotor | Open coast | |
|---|---|---|
| April – May | 8 – 15 m | 15 – 25 m |
| June – August | 10 – 20 m | 20 – 35 m |
| September – October | 15 – 25 m | 25 – 40 m |
| After heavy rain | Drops sharply for days | Less affected |
September and early October are the best diving of the year — warmest water, best visibility, and the boats are no longer competing for space.
The wrecks
- Tihany — a Hungarian steamer sunk in 1917, lying around 30 – 40 m off the Luštica coast. The signature dive here and one for experienced divers.
- Goritzia — an Italian freighter, shallower, broken up, good for penetration training.
- Patrol boats and small craft scuttled around the bay, several within recreational limits.
- Submarine pens at Rose and Luštica — cut into the rock for Yugoslav navy submarines, and divable at their entrances.
Montenegro's naval history means the seabed is genuinely littered. Some sites are protected and require a permit through the dive centre, which they arrange as routine.
Caves and walls
The outer coast around Luštica, Žanjice and Mamula has caverns, swim-throughs and drop-offs. Visibility there is Adriatic-standard — twenty-five metres is normal in September — and the terrain is more interesting than the inner bay.
Mamula island itself, the Austro-Hungarian fortress, has diving around its base among the fallen masonry.
What it costs
| Single guided dive with kit | €45 – €65 |
| Two-tank boat day | €80 – €120 |
| Try dive / discover scuba | €60 – €90 |
| Open Water course | €350 – €450 |
| Wreck or deep speciality | €200 – €300 |
Centres operate out of Herceg Novi, Bijela, Tivat, Budva and Bar. Most run from April or May to October.
What you will see
The Adriatic is not a reef sea. Expect octopus, moray, scorpionfish, sea bream, occasional grouper, nudibranchs on the walls, and a great deal of very good rock architecture. The wrecks are the draw rather than the fish life.
Practical
- Bring your certification card — centres check it properly
- Insurance — check that your travel policy covers diving to your planned depth; many exclude it
- Nearest chamber is in Croatia; centres know the evacuation route
- 5 mm suit even in August, because of the layer
