First opened in 1875, Kolkata’s 16-hectare zoo includes lawns and lakeside promenades that are very popular with weekend picnickers, hence all the rubbish. Bus 230 from Rabindra Sadan passes outside. Directly south of the zoo entrance, the (private) access road to India’s National Library loops around the very regal Curzon Mansion , once the colonial Viceroy’s residence. Around 1km southeast, the delightful Horticultural Gardens offer some respite from the traffic rumble.