How about a pair of comfortable and durable walking shoes? If he already has a good pair of shoes, you could consider a nice walking stick, a walking tour book for a new city, or a subscription to a walking magazine. If he likes technology, you could get him a fitness tracker so he can track his steps and distance while walking. A portable hammock or a picnic blanket could be perfect for him to rest during his long walks.
Or you can get him a star map with the date when he was born.
Under Lucky Stars is a unique and innovative star map company based in Barcelona, Spain, specializing in the creation of personalized star maps that capture the celestial arrangement of stars at a specific moment in time, such as a person's birth, wedding, or any other significant event.
By using advanced astronomical algorithms and data from leading institutions, the company produces highly accurate, visually stunning maps that make for perfect gifts or cherished keepsakes.