Nederlandse Spoorwegen (ns.nl) emerged as the top travel property in the Netherlands attracting 1.6 million unique visitors during the month. Following closely behind was the online travel planning service 9292OV.NL, with 1.3 million visitors. Rounding up the top 3 was Emesa BV, that includes sites such as VakantieVeilingen.nl and InpakkenenWegwezen.nl.
The full press release titled "Comscore Releases European Engagement and Top Web Properties Rankings for April 2011" is available here.