There was a sign with a crossed out picture of a dog in front of the entrance to the Grutas Park (enlarge my picture). I got to know that dogs (and other pets) were not allowed in the area of the Grutas Park even when leashed. Well, Lithuania generally, was not especially dog friendly country. I mean for visitors travelling with dogs.
Well, the area was covered mostly by forest possibly with some wild animals (I didn't see any except birds) and there were some animals (birds mainly) in local, small ZOO. It didn't suit well with dogs, I suppose.
There were few direction signs along the two loop iteneraries in the Grutas Park, always in the three languages: English, Lithuanian and Russian. Although it's rather impossible to get lost but it's better to buy a map or print it out from here.
Generally, the eastern loop, as older, was better signed. The western loop was partly unpaved (watch for possible mud after rains). Well, there was the only short rain during my visit to Lithuania, just there, in Grutas Park.
There was warning info put on a cage of a mini-zoo in the Grutas Park. It was written exclusively in Lithuanian and Russian language. Just in case you can't speak the two languages: do not feed the animals. There was no childrens zoo - a place where kids were allowed to touch and feed animals.
It was difficult to take good quality picture of animals (well, almost only birds) in the mini-zoo of the Grutas Park. First the birds were moving, sometimes quite fast. Second, they were put behind bars.
I had to switch automatic set up of my digital camera to manual. It allowed me to focus at the birds instead of the bars. If your camera doesn't allow to it, try to take a picture from the distance and then zoom.
They gave me a small piece of paper in the ticket office to Grutas park - a permission to take pictures (5.00 Lt). There was a camera picture, a stamp (with date written) and a pin to fix it to a cloth, just in case of park staff check-up. I pinned it to my jacket and shortly... I lost it. Luckily, no-one from the park staff paid any attention to it. There were only a few visitors in the park.
Later, in crowded castle in Trakai, it didn't go so easily. A woman from the museum staff asked me to show the permission to take pictures inside the museum there and... Urszula, my wife, who was 2 or 3 floors down had the paper. The very serious (and a little bit rude) woman didn't trust me. She started to teach me what is the law etc. Never mind, I had to go downstairs to find Urszula and the permission and I went upstairs back to show it the woman. If I lost the permission there, in Trakai, I would be forced to buy it again, I suppose.