Another site of early railway enterprise to be upgraded to 2* before benefiting from restoration (which would remove it from the 2024 at-risk register) is the S&DR [Stockton & Darlington Railway] coal drops, located in Shildon's Locomotive museum. After it was upgraded in 2021 […], 2022 research by Historic England found that the drops, constructed in 1847, were the world's first attempt at mechanising locomotive refuelling. The drops worked by chaldron wagons being taken up the incline, and their loads dropped down chutes into tenders of steam locomotives waiting below.
Source: wiktionary