St Joseph Cathedral in Guwahati calls itself a Co-Cathedral. I still need to figure out which cathedral it is partnered with.
This particular church is Roman Catholic, but there are many denominations practicing in the North East, so there are tons of churches around. (A google search for churches in Guwahati turned up 20 times as many churches as in Delhi.)
Mass on Sunday is at 7:00am in Hindi and Assamese. English service is at 8:30am and 5:00pm. Daily services are at 6:15am in Hindia and Assamese and 5:00pm in English.
Attending mass here was very similar to attending mass back home. There was an atmosphere of peace and prayer in the church. It felt like a church, unlike the prayer group meeting feel at St Lukes in Delhi. Wish the choir had instrumental support, but perhaps the organist was on leave or attends evening mass?
After mass, everyone gathered outside to chat in groups and catch up on events of the week after praying at the grotto. I'm not someone who generally socialises after mass.