Cathays and Roath are the two major student housing areas for students at Cardiff University. Both are close to the Park Place campus, and are packed with shops, bars and takeaways, but there are a few things to bear in mind when deciding which area to choose. This isn't a complete guide by any means but hopefully it will give you a few things to bear in mind when choosing where to live.
Cathays is ideal for students studying subjects based around Park Place such as History, English, Law and Psychology. It's also the area closest to Cardiff University Students Union. Incidentally, the union's Advice and Representation Centre (ARC) is a great place to go for more detailed information on the nuts and bolts of renting a house: contracts, tenancy agreements and so on. At most, houses in Cathays are around a twenty minute walk away from Park Place.
I lived on Miskin Street in my second year and found it to be a really good location, even if the house itself had its faults. Lidl and the Woodville pub were just around the corner, the SU was five minutes away and it was a ten minute walk from the Arts and Social Studies Library and lecture halls. Despite being a long student-filled road, it wasn't noisy at all and there was always plenty of space to park cars - you'll need to get a permit from the council, though.
Salisbury Road joins on to Miskin Street is another student hub, with numerous takeaways and newsagents, a doctors surgery and a small Tesco. It's also home to Koko Gorillaz and Gassy Jacks if ever you fancy a drink or a cheap burger.
Other roads in Cathays tend to be busier and noisier at night. Traffic on Cathays Terrace and the sound of freshers heading back up Column Road to Talybont after a night at the SU may keep you awake for a bit some nights. If you live at the end of Column Road closest to the Student Union, be prepared to be harassed by election candidates every time you step out of your front door during campaign week!
Roads further up Cathays Terrace such as May Street and Minny Street tend not to be as studenty, and you may find that your neighbours are regular people with actual jobs and families and stuff. This is true of the Maindy area as well, which is closer to Talybont and the Maindy Leisure Centre, which has a pool and a gym. It's quieter here, but you'll have to wake up that little bit earlier to make it to classes on time.
Further away from Park Place and therefore a bit less studenty, Roath is quieter and, in my experience, the houses and flats here are a bit nicer and around the same price. Live here and you'll be walking for between twenty minutes and half an hour to get to lectures or to town. City Road, Albany Road and Crwys Road are the biggest and busiest in the area and you live here it'll probably be in a flat above a shop. Bear in mind that your more likely to be disturbed at night if you live above a late-opening restaurant or bar than if you live above a barbers.
On that point, there's no shortage of places to have a bite to eat or an evening meal, and if you want to cook for yourself Albany Road has a Tesco and Iceland, as well as Superdrug, Boots, Savers. Home Bargains and a wealth of smaller shops selling everything you need. City Road has takeaways and convenience shops including Spar and Tesco. There is an ambulance station at the bottom end of the road so you hear sirens quite regularly, but other than that it's very quiet. Streets leading off City Road are more peaceful still, and it's here that the majority of parking spaces will be found. If you live on City Road proper you may struggle to find a space right outside your front door.
I live in Roath at the moment and find the area to be nicer than Cathays, but I do miss the shorter walk to uni that I had when I lived on Miskin Street. If you don't want to be as in the middle of everything - maybe a postgrad or final year student - then I'd highly recommend any rooms in Roath if they're available.
I hope that helps! Apologies for not mentioning Heath or student housing areas for Atrium or Cardiff Met students. I thought it was best to focus on areas I actually know about!