The resort town of Calella boasts a high level of tourist safety. The only problem with Calella is the pickpockets that operate at the train stations and beaches.
It is recommended not to carry a backpack behind your back (prefer belt bags), keep valuables in a hard-to-reach place (a camera around your neck is a great bait for thieves), buy passes for all types of transportation (on the one hand, you save money, but on the other hand - you will be spared the need to take out your wallet every time).
Also, be careful while sea bathing and follow all safety rules while boating and yachting, in particular, use a life jacket.