https://www.theguardian....hday-box-tunnel-bath-sun

The idea is very ancient. The Maeshowe cairn, a neolithic (ca 5,000 years ago) underground tomb in Orkney (where my father's family came from) has its entrance passage aligned so that the burial chamber is illuminated by the sun at the winter solstice. There are various other examples.
But not many get the chance to memorialize themselves this way.
Happy Birthday Isambard.
Jabez