(Frostburg, Maryland-AP) -- It's a common sight for travelers along Interstate 68 near Frostburg, Maryland -- a web of steel that should someday resemble a giant boat. But not even the builder knows when anyone will be able to climb aboard. The full-size representation of Noah's Ark is nearing it's 20th year of construction. Three years have gone by since the last beams were laid in place. Pastor Richard Greene relies on donations to continue the work. That means there is no timetable to finish the ark. Greene says -- quote -- "as God provides, I build" -- unquote. Greene believes the completion of the ark will be a sign that Jesus will return soon.