Fwiw the remaining sculptures in Greece aren't left outdoors at the actual Parthenon site either, in order to protect them from damage (though they are nearby).

Fwiw the remaining sculptures in Greece aren't left outdoors at the actual Parthenon site either, in order to protect them from damage (though they are nearby). The Acropolis Museum [1] stores 5 of the 6 Erechtheion caryatids (the 6th is in London), as well as the portions of the Parthenon frieze that weren't removed by Lord Elgin. On the acropolis itself, the Erechtheion has replica caryatids, while the Parthenon is "bare" with no frieze or pediment. The museum is arranged with the intent to display the complete set of pieces, with blank space deliberately left for the missing items, so in terms of technical housing I don't think there's a problem (this was part of the political motivation for building the new museum, to have a credible facility for the sculptures to be returned to). The caryatids are currently arranged as a set of six, but with one spot empty, and the frieze is laid out as a full-sized display of the entire frieze, with the pieces that the museum possesses inserted into their correct place, and plaster casts used as placeholders for the missing parts. [1] https://en.wikipedia.org/wiki/Acropolis_Museum https://en.wikipedia.org/wiki/Acropolis_Museum