What a great question. It really made me think. I have a memory box too but it is filled with visual and tactile things that represent happy memories. I can take my box into the closet with me. I found a tiny (3x4inch) stuffed arm chair and a lovely 'carpet' in a craft store in the dollhouse section. I used three plastic shot glasses with covers (party supply store) and filled one with little shells, (I love the sea),one with tiny buttons(running them through my fingers into my lap helps with deprivation memories).. In the box there are two lama finger puppets. An eastcoast Indian medicine bag(I am a small part Wampanog) with corn, stones and crystals, a little bell for joy, a tiny pinecone, three animal protectors- a flourite bear and a stone turtle and a tigers eye owl and a clear crystal frog-a spiral top of a shell to remind me that therapy is like riding a spiral in and down then up and out again and again. I can set up a small medicine circle in front of me if I need to. I have a little doll dressed historically like my home town. a couple of icons. The box has four glass sides and a glass top so I can see everything without needing to get them out.
Maybe since you love the outdoors you can collect things that you love to handle that will remind you of the good places you've been. Can you find a picture of the Milan dome, on the net maybe?