Here are some websites that I found useful when I researched my Tenerife holiday.
1. Trip Advisor is not just for Tenerife but anywhere in the world really. You just select the area (country, resort) you are interested in and you can see a whole wealth of information about it, mainly as a result of other people's reports. So you get true-life experiences rather than glossy advertising blurb. Rather like this web site, really!
Added to which you can subscribe to their newsletter for free. Let's say you are interested in hotels in Puerto de la Cruz; they will send you updates whenever there is something new on that part of their site (eg another review). It's easy to subscribe and easy to unsubscribe. Whilst their site is advertising sponsored they seem to have no interest in sending you stuff you're not (any longer) interested in.
If you make use of their services it might be nice just to add a review of the resort or hotel you've been to, that way everyone benefits.
2. Holidays Uncovered. Once again, covers the entire world and gives holiday makers the chance to "sound off" about their holiday, and rate the hotel, accommodation and location.
Some people go overboard, either on the praise or the critisism, and the fact that one holiday paradise was another's holiday from hell shows that you can't please all the people all of the time. But it's extremely useful to get other people's opinions of the whole holiday scene.
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