Founded by Australian brothers out of Austria, social travel startup TourRadar is today announcing a ‘strategic round of angel funding’ from a couple of heavy-hitters from the travel industry and beyond.

The size of the round isn’t being disclosed, but investors include Erik Blachford, the former CEO of Expedia, and Jörg Trouvain, former CEO of popular European hotel review platform HolidayCheck.

Other backers who participated in the financing round include Christoph Prinz (who sold aviation software firm ‘f:wz’ to Sabre Airline Solutions), Markus Wagner (i5invest incubator) and Speed Invest (a 10 million-euros ‘super angel’ fund based out of Vienna).

TourRadar lets people search, compare prices for and directly book group tours across the globe, enabling travelers to co-organize and meet each other during multi-day trips to boot.

Travis Pittman, co-founder and CEO of TourRadar, says:

The $89 billion tour industry needs a consumer website where travelers can research, choose and book tours from hundreds of operators from all over the world.

This funding will enable TourRadar to become the pre-eminent online marketer of multi-day trips. With our mix of tour information, user reviews, social messaging and e-commerce we offer travellers the best way to find and book their perfect tour.

Founded in 2010 by Travis and his brother Shawn, TourRadar works directly with over 500 tour operators worldwide, offering some 20,000 tours in 220 countries.

I’m informed that the longest tour one can book on the TourRadar website takes 448 days and goes from London to Sydney via Africa, the Middle East and Asia. I probably can’t afford it.

In addition to its website, TourRadar hosts an array of affiliate partnerships and a suite of Facebook and mobile apps designed to assist the consumer’s travel research and purchasing experience.

One of them, dubbed ‘Meet Others’, is an app that travelers going on the same trip to get in touch with each other before the tour starts. It’s already being used by hundreds of tour operators, TourRadar claims.

The proceeds of the funding round will be used to build out its marketplace and to enhance said social applications.