 Complete the following phrase:  Best described as labyrinthine, Topolnița Cave is a difficult cave to explore even for experienced cavers. Access for tourists is permitted only once per year, on a feast day in August, where guides lead tours into the cave to view the Racoviță Gallery. Otherwise, the cave is gated and access is only available by permission of the Romanian Academy. In the 1980s, there was some government interest in adding tourist-access features such as stairs, railings, and electric lights, but funding fell through before the 