I usually don't buy those things called 'must visit' cos when it comes to my trip, well...it's mine, it's totally up to myself where to go, what to do or what to eat. But I take and give recommendations tho, and House of Sampoerna is the one most recommended to be visited in Surabaya. Not only it's a great place with nice atmosphere, it's also FREE!!! :D You only need to be more than 18+ years old to get inside, and they also have city sightseeing tour everyday, check out the schedule here:
http://houseofsampoerna.museum/e_sht_main.htm
The main attraction is the making of hand-rolling cigarettes using traditional equipment at a speed of more than 325 sticks per hour. I felt like viewing fast-forwarded movie, but LIVE!! And it's not only museum displaying anything related to Sampoerna tobacco company, but there are also art gallery, gift shop where you can post your own postcards and an art deco cafe :)
