Mike Addis and his wife, Catherine Weightman, have built an eight-foot by eight-foot advent calendar in the lounge of their Northern Street home using more than 450,000 Lego bricks.Mike is also the man behind the Harry Potter and Hogwarts construction in the window of the Oxfam Book Shop in Huntingdon. The advent calendar has 24 windows, which all open and light up to reveal various scenes and locations, including a Christmas dinner, Wicken Fen, a group of snowmen and a gingerbread house. He also made a kingfisher, a postbox, and a stained glass window, which, he said, were difficult to create. Mike admitted this was his most ambitious project to date and it took him and Catherine two months to complete. I have been making Lego creations for the last 25 years and this is the biggest yet, he said. The gingerbread house alone took about 1,000 bricks and some of the figures and the details in the advent calendar were very complicated and it was quite stressful. Over the years, Mike, aged 60 and Catherine, 55, have built a Victorian dolls house, Daleks and a polar bear. Mike started making lego creations when his children were small but found it relaxing so he carried on and became more ambitious. Mike is also a volunteer at the Oxfam Book Shop and offered to create the Harry Potter-themed window. The creation comes complete with the moving staircases, the dormitories and the great hall. It is made up of more than 70,000 pieces of Lego and took Mike three weeks to finish. Book shop manager Geoffrey Stalker said: There has been a lot of interest in the window and it is great to see people stopping to have a look and taking pictures. Being at the end of the High Street we welcome anything that gets people to come down to this end of the town. Mr Stalker said the shop was always looking for donations of Lego, which sold well and could be used to make the window displays. INFO: Oxfam Books is based at 101 Huntingdon High Street. If you have any Lego you would like to donate, take it along to the shop.