The BRIO Adventure Tunnel is a fantastic accessory that will make the wooden train sets even more fun. Shaped and colored like an Alpine tunnel, the sturdy plastic tunnel has a realistic stone-effect surface and flowers. Open at both ends under brick-effect arches, with BRIO track passing through it, the tunnel interlocks easily with other BRIO sets. But the real appeal of the tunnel only becomes apparent once the 2 x AA batteries required (not included) have been fitted in the safely concealed cavity underneath. (A screwdriver will be required to open and close this).Just push the button, or pass a BRIO train equipped with the necessary magnet through the tunnel, and one of four adventure sounds will bring the tunnel magically to life. A very loud "toot toot" may follow or the echoing sound of a train rushing through a tunnel, or even sounds of people at work inside. Beware, however, though the noises turn themselves off (the longest lasts for around 7-10 seconds) they are very loud. Children will love this feature for realistic play, but for less enthusiastic parents there is an "off" switch. The tunnel also has a flip-up bridge across its top for use with the BRIO people (sold separately). Warning: Not suitable for children under 36 months.All in all, this adventure tunnel is a novel, lively toy that children really love. It certainly adds another dimension to the traditional train set format and will soon become a favourite addition to your little station master"s kit. --Lucie Naylor