Trondheim is among other things famous for all it's history and tourist attractions connected to it (like the national cathedral, The Nidaros Cathedral), much of it connected to the vikings. Back in the middle ages, the city was capital of Norway and called 'Nidaros' before Norway went under Danish rule. The city was founded by Olav Tryggvason in 997.
Trøndelag is also known for it's own "genre" within rock called trønderrock. The genre in itself isn't defined, and it's only definiton is music from groups or artists from Trøndelag. Some notable names within this category is the group DDE, and Åge Aleksandersen. Trondheim made itself even more noticed as a musical city when Norway's national museum for rock music, "Rockheim" (translation: Rockhome), was built there a few years ago. A world-class museum of music and musical instruments, containing a grand collection of musical instruments from all-through the times, called "Ringve Museum" is also located in Trondheim.
Trondheim is located right by a large fjord, Trondheimsfjorden. There are many advantages Trondheim gets from this, like the tourists travelling with the ferry, and a constant supply of fresh fish.
People from Trondheim and trøndelag are modest and depressive. The only loud people are people singing dark heavy metal.
Some people say Trondheim is really beautiful, but Bergen is by far more so.
Honky dude: No, it's just boring there. Let's go to Bergen in stead!