THALAMAC

So, one day, a mother and her progeny (her two grown daughters and a granddaughter) decided to drive up and down the Northeast Coast of the USA... They started near Baltimore, Maryland, and turned around at Prince Edward Island, Canada. Read of their adventures that spanned thirteen days! What does "THALAMAC" mean? Thelma and Louise Across Maine [later adding] and Canada. Why? Ask the mother.