How lively/how many things to do are usually in the city during both night and day?

[gusjc]

Hi. I'm looking into moving to somewhere in Europe with my partner, and Copenhagen is looking like a very likely option.

However, having lived in big cities before (Buenos Aires, New York City), I'm used to having something to do all the time. I really like having a seemingly endless number of bars, restaurants and cool spots to spend an evening; and concerts, museums, cultural events to go to during the day.

I've read in many places that Copenhagen has a "small town vibe" to it, so I'm afraid it's way too relaxed for me. How would you describe the variety of daytime activities and nightlife in the city?

Thanks!