Darryl and Kathleen Toupkin of Scottsdale have gone to the far edges of the earth — literally — to accomplish their goal.

They visited their first national parks unit, which also includes national monuments, historic sites, trails, waterways, recreation areas and preserves, in 1986, back when there were 300-plus of them.

Nearly four decades later, with 431 on the list, they’ve finally visited them all, having ended their journey at St. Croix Island International Historic Site in Maine.

It’s been a circuitous journey.

They’ve had to double back on routes multiple times to catch newly designated sites — even learning of a newly created one in Illinois while traveling to Maine (thankfully, they’d already visited what is now the Springfield 1908 Race Riot National Monument).

The Toupkins don’t just make a stop at the visitor center to check locations off the list. They typically hike, climb, bike or boat through the parks. They sign up for ranger talks and tours.

They fully soak in........

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