I read this a while back and it is one of the most entertaining reads I have had in quite some time now. It is based in Ireland and the author did extensive research into the real places that are told about in the story.
I am sure that you and your kids [or grand kids] will enjoy it as much as I did.
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A Time for Travel ~ The Christmas Project is about four cousins who invent a time travel machine over Christmas vacation. They set the time for 200 years in the past and set the location for the MarbleArchCaves in Northern Ireland. That is not where they end up!
Follow Brooklyn, Caleb, Genevieve, and Kennedy as they explore the castles and caves of ancient Ireland on their grand adventures. What will they do once they get there and their time travel machine doesn’t work? Will they find the leprechauns, dragons, fairies and unicorns they are looking for? Will they get home?