Lund and Malmo

Skip Malmö and spend a day in Lund. You are right, it is a charming town that can certainly keep you entertained for a day. Malmö is less interesting in comparison.

I visit both places regularly and if I had to pick one to recommend, it would be Lund.
Lund is a lively and historic university town, and if that sounds like your kind of place, you can easily fill a day trip there with sightseeing (Lund cathedral, Kulturen open air museum, etc) and just wandering around the town and campus, stopping for a meal and/or a coffee and cinnamon bun (try Broder Jakobs on Klostergatan) and so on.

Malmö is much larger (Sweden's 3rd largest city) and has more of an urban feeling. Formerly an industrial city, there is now an artsy/hipstery, youthful vibe and it has some interesting modern architecture, lots of good restaurants/cafes and shopping etc. Although there are a few picturesque squares and some interesting sights/museums, there's nothing I would really consider 'must see' and I don't think it will add too much to your trip if you are already going to be staying in Copenhagen. That being said, if you find yourself with extra time on your hands, it's easy enough to just hop off the train in Malmö on your way back from Lund and have a quick stroll around the historic parts (less than 10 minutes walk from the central train station).

I was in Copenhagen in August and did a day trip to Lund. It's a cute town to walk through. The cathedral was under scaffolding for restoration while I was there but the interior was open. I too considered Malmo, but Lund was more what I was looking for.

A good option for a meal in Lund is to try the falafel. Not a very typical Swedish dish but has gained notoriety in Lund as a cheap and quick lunch that is popular among the town's students. There are many places to consider, one popular is Clemens falafel close to Clemenstorget.

If you feel that Lund is not enough for a day and want to combine it with another town, consider Helsingborg or Ystad instead of Malmö.

As mentioned, Malmö is an industrial city that historically has had (and still has) a lot of heavy industries, especially shipbuilding. Lund on the other hand has been the more "educated" town with the cathedral and university. Locally it is sometimes said that the distance between Malmö and Lund is "the circumference of the earth, minus 20 km".

I was in Lund early September and really enjoyed the town. I spent some time at Kulturen, an open air museum that was interesting and informative. I also toured the campus as I had contacts there and was impressed by all the historic and interesting buildings that are part of campus and around town. I stayed in Lund and had fantastic Swedish meatballs at Gastro|nome not too far from the train station. You could certainly have time to stop in Malmö if you want but I think you’ll really enjoy spending more time around Lund.