Every Friday, we help you navigate the week’s most important and interesting travel news stories.

Hold on folks, we’re in for a rocky ride

In Portugal, a partial air traffic controller strike led to hundreds of flight cancellations to and from Portugal on Thursday and Friday. Additional strikes are planned for 24 and 25 May. Passengers are entitled to compensation under EU law. [Which.co.uk]

Irish low-cost carrier Ryanair is closing its website for maintenance this weekend. Passengers travelling this weekend must check-in online by 16:00 BST on Friday or face a 60-euro surcharge. [BBC News]

Is now the time to vacation in Greece? No. Hotel prices will remain fixed through the summer because major tour operators have already made their bookings. But if the country leaves the euro, price devaluations could make everything much, much cheaper for tourists. [NPR News]

Amazing things that should happen more often

Many museums worldwide will offer free admission, late nights and special events today and tomorrow as part of International Museum Day (18 May). Find details on the global website or in your local arts and events publication, such as Time Out London. [International Council of Museums]

East and West Africa's first metasearch site for hotels and flights, Twendetwende, debuted this week. The new Kenya-based site lists more than 400,000 hotels in Africa and across the globe. [Tnooz]

The best and worst airlines for redeeming frequent flyer miles were revealed by travel consultancy IdeaWorks. Delta and US Airways were at bottom of the list of global airlines. But Southwest has the best availability for booking reward flights through the summer. Since last year's survey, British Airways showed the most improvement in available reward seats. [WSJ]

In-flight entertainment
Photos and videos that went viral on the Web this week

This week, readers' favourite link was to a beautiful slideshow of the United Kingdom's glowing vistas. Photographer Jason Hawkes shot the night-time images from a helicopter to capture unusual angles. [In Focus]

By year-end, Virgin Atlantic will permit cell phone use on flights between New York and London. But passengers will pay a whopping $1.20 per minute to use their own phones to make calls and texts, which will be routed through a special technology that's being installed on 20 aeroplanes. [Daily Mail; CNET]

Our most re-tweeted link of the week was an essay by Montana-based Walter Kirn, author of the novel "Up in the Air", about how he believes "hiking is better with an iPad".

Need inspiration for your own hike? Check out this Google Maps mash-up of the world's most interesting remote places. [Outside]

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