You Can visit Sundar wildlife sanctuary..its located in south delhi. It also has a nice cafe.
Jesus Place - Gadaipur, Asola Bhatti Wildlife sanctuary
Okhla Bird Sanctuary- NOIDA, Botanical Garden- NOIDA, Lodhi Garden - Central Delhi, Old Fort - Pragati Maidan, Yamuna Biodiversity Park- North Delhi, Kamla Nehru Ridge- North Campus
There's this lane near civil lines metro station, which you once enter will take you away from all the traffic and noise.
Garden of five senses, Budhha Garden. Check my photo, have been there.