The Tunnel of Hugsy Goode

Nobody believed Hugsy Goode when he prophesied that a tunnel lay beneath the alley until--generations later--Nicholas (alias Copin) and Timothy (alias Tornid) decide to explore. And lo and behold, right under the vine-covered hole outside the house where Hugsy Goode used to live, they find an entrance to adventures beyond their wildest dreams.
A sequel to The Alley.

Eleanor Estes (1906-1988) grew up in West Haven, Connecticut, which she renamed Cranbury for her classic stories about the Moffat and Pye families. A children's librarian for many years, she launched her writing career with the publication of The Moffats in 1941. Two of her outstanding books about the Moffats--Rufus M. and The Middle Moffat--were awarded Newbery Honors, as was her short novel The Hundred Dresses. She won the Newbery Medal for Ginger Pye.