International adventure awaits retirees with the time and budget to pursue it, but some cities are better hosts than others, according to a new report by personal finance website InsureMyTrip.

Civil strife, crime, long lines, inaccessible tourist sites, a lack of public transportation, and scarcity of medical facilities staffed with physicians who speak English are just some of the potential pitfalls that can turn the trip of a lifetime into a never-ending nightmare when the unexpected happens, according to the study.

To help seniors find suitable locations, InsureMyTrip, the Warwick, R.I.-based insurance platform, ranked 50 cities worldwide across the four categories of tourism, well-being, mobility, and demographics using eight metrics: quality of things to do; selection of senior tours; available of healthcare; peacefulness, which includes safety, crime, security, and conflict; ease of walking; public transportation; average population age; and population density.

Here, in ascending order, are the study's top 10 best cities to visit as a senior.

10. Helsinki, Finland

Helsinki, the capital of Finland and its largest city, offers visitors free walking tours. With Radar.com reporting only 10 senior tours to Helsinki, the city scored 4.43 out of 5.0 in tourism and 79% out of 100% in well-being. The population has an average age of 43.