Jijibaba Yuusha Party Saigo no Tabi: Oita Saikyou wa Iroasenu Mama Mirai e Susumu you desu

Even great heroes eventually grow old. Decades after saving the world, a band of brave heroes now live quietly in peaceful retirement as their final days await just beyond the horizon. Knowing time is short, Ferd the Hero longs to reunite with his old friends and meet his great-grandchild while he still can. In the company of his wife, Elrica the Saint, Ferd sets off on a transcontinental journey to see their comrades and finally visit their family abroad. Yet their last hurrah is bound to be anything but ordinary. After all, wherever legends of great tread, great trouble is sure to follow. Only one question remains: Is there any problem the greatest heroes of their age can't solve?

(Source: J-Novel Club)