I see that the trams within the park don’t operate until April. Can you see much of park just walking. Or do you need a bike?
Walking the whole arboretum would be a major hike. There is public trans to near the entrance, and there is a good motorized tour through the whole thing (which is large).
There is a bike share at the entrance to the arb. I walk my dogs there often, and there seem to be many bikes at the entrance most of the time. For a pedestrian arriving at the entrance, I would advise getting a bike, there are many interesting areas, separated by what would be significant walks between.
If you want a few hours of walking, it's easy to see several quite distinct areas.
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