I have a few friends from IISER Pune. Here are some of the points that they have shared from their experience. 

• You can roam around the campus freely. Every building is open always.
• There are no bizarre rules regarding dress codes.
• There is no specific entry and exit time on campus.  
• The rules are gender-neutral. There is no unreasonable rule regarding any gender. Although safety of the students isn’t compromised.