Dolphins below the City

I have been reliably informed by a friend who used to work at the ‘Underground’ bar, below the Town & Country Club (now Creation Night Club), that in Victorian times the building was sometimes used to host Circuses, & with this in mind, tunnels were built from the cellars to the Station, so that dangerous animals such as tigers could be transported there without putting the public at risk.
I have also heard that, on occasions, the tunnels were flooded with water, which allowed dolphins to swim, underground, below the city, & emerge to give displays within the building.