Flakk Camping

auto-translated: Beautifully located at the harbor, but unfortunately very noisy. The site is very uneven. Sanitary facilities are very basic, but okay. However, the price is too high.
The receptionist is nice and very helpful.

auto-translated: Great campsite for visiting Trondheim. The sanitary facilities were clean, but the shower cubicles were small.
The view over the fjord was beautiful. We weren't bothered by the ferry at all. It's electric, so it's pretty quiet.
The kitchen was limited to two electric hotplates.

auto-translated: In general, I recommend this place. You can accommodate yourself even outside reception hours - then you pay for the accommodation the next morning or send the details in an SMS.
The cost for a tent place for two people with a car is about NOK 355. The price includes a lot of toilets and showers with hot water!
The kitchen is also very nice and equipped.