Question

What's their Special attractions? (Which cities are your best bet)

It depends on what one is looking for. Best is a very relative term.

Since this is not my area of expertise, I searched Google under the key words "<I>Puerto Rico attractions</I>" to get these possible sources:

http://www.expediaguides.com/default.aspx?tla=SJU&eapid=13172-1&kword=PTG:Puerto+Rico+attractions&gclid=CJr1pLn-0IgCFQIDGAodVwjJQQ
http://www.dollarman.com/puertorico/sightseeing.html
http://www.tripadvisor.com/Attractions-g147319-Activities-Puerto_Rico.html
(Broken Link Removed)
http://www.viequestravelguide.com/puerto-rico-vacation.html

If you do a similar search, you will find many more sites.

I hope this helps. Thanks for asking.

Thank you for using the Jiskha Homework Help Forum. It looks like you do not yet have the site for the CIA Fact Book:

https://www.cia.gov/cia/publications/factbook/geos/rq.html