Even though Timmermans is owned by the British giant, Anthony Martin, the beers are still made the way they have been for centuries. They have a great site, so you can read more there if you wish.
My education about lambic beers has been a bit lacking, so they have not been common on my tastings. They are spontaneously fermented by the wild yeast that inhabit region of the country. Lambic beers have been brewed in this manner for hundreds of years.
It was a very refreshing way to start our day.