Grič Tunnel was built in 1943, during World War II and connected to Zagreb tunnels. Its primary purpose was to shelter civilians from frequent bombings during WWII and the Croatian War of Independence.
After all, it is a part of a network of Zagreb tunnels under the Upper Town. But the only one open to the public!
You can find the tunnel entrances as they are marked with Zagreb coat of arms. Once you look at Zagreb coat of arms on the rooftop of St. Marks Church, you will notice the underground, secret door under the castle. Symbolising the entrance to hidden Zagreb network of tunnels.
Stories and legends speak of secret underground passages all over the city. One of them speaks of the great 1880 earthquake. When it is said most of the tunnels disappeared, containing the church gold. https://www.visitzagreb.hr/zagreb/gric-tunnel/
Porta Orientalis is their Roman name. These gates were used to enter the palace from the east towards the west, through the main street, decumanus, all the way to the Iron Gate and to Pjaca, the central city square.
The Silver Gate was more modest in its decorations than the Golden one, and it was closed from the Middle Ages till 1952, only to be thoroughly reconstructed during the destruction of the Baroque church Dušica. On each side of the gate, the remains of the octagonal towers are visible, hence making it easy to imagine the beauty of the construction and the strength of the control over the entrances from the north, east and west. Entering through those gates the passersby, even today, have the opportunity to walk the original ancient pavement on decumanus, walked also, so many years ago, by the Diocletian's subjects.
Silver Gate has recently enriched its history with the greatest event for all the Split Catholics when in the year 2000 Pope John Paul II passed through them admiring the beauty of St Domniuses Cathedral where he later prayed. https://visitsplit.com/en/522/the-silver-gate
Near the road Rovinj-pula, about 2 kilometres far from the centre of the City of Rovinj, in the locality of Monfiorenzo, is situated the quarry phantasy, a geological park of remarkable beauty and importance. According to the expert opinion of numerous scientists, it is one of the most significant natural monuments in the world in the perspective of the karst phenomenon. The lime-stone of the quarry phantasy, like the open book pages, illustrate the history of the evolution of the terrestrial crust.
Various layers give evidence of the existence of the fossilized meadows consisting of sea-weeds, which, blended with lime-stone silt, were drifted on the shore by strong currents during the last 130 million years.
The quarry phantasy will reveal to a more careful visitor a considerably big number of furrows made of black and white dolomiti layers. Furthermore, there are fissures formed by tightening and exsiccation of the silt that had been squeezed into the previously created sediment.
The lower part of these stony layers was formed below the sea level, while the upper part is the result of the high-tide. https://www.inforovinj.com/eng/rovinj/znamenje/monfiorenzo.asp
The entrance to the Old Town is through the Land Gate (Kopnena vrata) at the south of the Old Town. The gate’s front is covered by a triumphal arch built in honour of commander Leonardo Foscolo, who was instrumental in the defence of Dalmatia during the 17th century. https://www.visit-croatia.co.uk/croatia-destinations/croatian-islands/korcula/sightseeing-korcula/