Grenzstein - Istria Peninsula
The Double Reef here, just off Ishigaki, is a bit of a local secret, and we love it. It’s exactly what it sounds like – two parallel coral ridges running north to south, separated by a sandy channel about five metres deep. The outer reef wall drops down, but we stick to the top where the light is best. The real magic happens between those two ridges. It’s like a superhighway for fish. You'll often find big schools of Indian mackerel zipping through, sometimes chased by something larger. Keep an eye out for the smaller stuff too; the Dapple Coris and Three-spot wrasse are always busy flitting between the coral heads. We’ve seen some seriously chunky Staghorn coral formations here, and the Large meandroid brain corals are impressive. Visibility can be brilliant on a calm day, giving you a real sense of the reef’s structure. Our favourite time to dive it is mid-morning, just as the sun gets high, really making the colours pop. It’s a pretty easy drift, perfect for anyone who enjoys a relaxed dive with plenty of fish action.
- Location
- Istria Peninsula, Croatia, Mediterranean & Europe
- Coordinates
- 46.969520, 8.309720
- Type
- reef
Best Time to Dive in Istria Peninsula
The warmest water temperatures in Istria Peninsula occur in August, averaging 26.1°C. The coolest conditions are in March at 11.8°C.
Monthly Water Temperatures
- January: 13.5°C
- February: 11.9°C
- March: 11.8°C
- April: 13.4°C
- May: 17.0°C
- June: 22.4°C
- July: 25.6°C
- August: 26.1°C
- September: 23.6°C
- October: 20.3°C
- November: 17.8°C
- December: 15.8°C
Nearby Dive Sites in Istria Peninsula
- 100 Steps
- 1. Niederbayerischer Tauchsportclub Plattling e.V.
- 3 Zinnen - 18m
- A CAPELLINI - 11m (wreck)
- Accademia Blu Diving Center
- Allgäuer Taucherhof
- Allmannshausen: Naturschutzgebiet
- Allmannshausen: Seeburg
- Allmannshausen: Wasserwacht
- Allmannshauser Steilwand
- Almsee (reef)
- Alpenblick
- Alte Badanstalt
- Alte Brücke-Flurlingersteg
- Alte Julierbrücke
Nearest Dive Centres to Grenzstein
- 100 x 100 Diving - PADI, TECREC, DAN, EFR
- ACQUASUB VICENZA TEAM asd
- Albarella Diving Center SSDRL
- Apnea Slovenija
- Aquaemotion SSD SRL
- Aquanautic Elba - SSI
Marine Life in Istria Peninsula
Home to 48 recorded species including 28 reef fish, 7 sharks & rays, 3 other, 2 crabs & lobsters, 2 octopus & squid, 1 whales & dolphins.
Notable Species
- Corb (Sciaena umbra) - Reef Fish
- Cape Shark (Squalus acanthias) - Sharks & Rays
- conger (Conger conger) - Reef Fish
- Common lobster (Homarus gammarus) - Crabs & Lobsters
- Common Eagle Ray (Myliobatis aquila) - Sharks & Rays
- poor cod (Trisopterus minutus) - Reef Fish
- Blue Stingray (Pteroplatytrygon violacea) - Sharks & Rays
- Common smoothhound (Mustelus mustelus) - Sharks & Rays
- Painted Comber (Serranus scriba) - Reef Fish
- Wrasse (Coris julis) - Reef Fish
- Blackspotted Smoothhound (Mustelus punctulatus) - Sharks & Rays
- Damsel fish (Chromis chromis) - Reef Fish
- Leidy's Comb Jelly (Mnemiopsis leidyi)
- loggerhead turtle (Caretta caretta)
- Cowfish (Tursiops truncatus) - Whales & Dolphins
- Slender Seagrass (Cymodocea nodosa) - Seagrass & Algae
- hake (Merluccius merluccius) - Reef Fish
- Mullet (Mullus barbatus) - Reef Fish
- european squid (Loligo vulgaris) - Octopus & Squid
- common cuttlefish (Sepia officinalis) - Octopus & Squid
Recommended Packing List for Grenzstein
Based on average water temperature of 18.3°C, currents 2 cm/s.
- Wetsuit (3-5mm) - comfortable for 18°C water
- Mask - essential for every dive
- Fins
- BCD - buoyancy compensator
- Regulator - your most safety-critical piece of gear
- Dive Computer - tracks depth, time, and NDL
- Surface Marker Buoy (SMB) - essential for boat pickups
- Dive Torch - useful for crevices and colour at depth
- Underwater Camera - capture your diving memories