Sounds like our rock-hunting trips, although for those we are better off driving to Utah or Oregon or wherever in our own truck, where the boots and shovels and tools and packs and water jugs--and the rocks--can all be thrown in the back.

Our European trips often involve a high degree of museum weeniedom (see the trip we dubbed the "London Museum Death March" of 2003, when we went to the Aztec exhibit at the Royal Academy, the Courtauld, the V&A, the National Gallery, the National Portrait Gallery, the Natural History Museum, the Tate, the Tate Modern, and Hampton Court (skipped British Museum because had been there before and feet dead by then anyway).

For European trips longer than, say, 10 days, we are likely to check one bag.