After a year of lockdown London, an overnight in Hay has the ecstatic fall and rise of a nostalgic nocturne, the gentle diminution at dusk followed by the dawn crescendo of rooks, blackbirds, buzzards, wood pigeons and racing tractors.

It beats NW1's sunrise cacophony of car alarms and skip trucks. And my hour on the cinema stage chatting about Latitude with Simon Hancock made me realise how lucky I am to have been invited back to the Festival.

I've always seen Hay as the perfect place for a book's first night. Thousands of hours of research and writing and redrafting until brain cells are popping and caffeine ceases to work, culminate in this pretty wad of printed pages in search of the right moment.

For me, that moment will always be Hay. A border town is the right place to launch a book, to offer it up to unknown readers. And down on the banks of the Wye last night, with the muscled flood sliding by, I was able to imagine the river carrying my story downstream past the turrets of Goodrich and rapids of Symonds Yat to the tidal Severn and the ocean crossed by the scientists who sailed in 1735 to South America on the Latitude expedition. So thank you, Hay. Thank you for keeping the show on the road.

The geographer, explorer, author and broadcaster introduced his new book, Latitude, at Hay Festival 2021, published 25 years after Longitude. Other titles of his include Why Geography Matters: a brief guide to the planet and The Making of the British Landscape. Watch the event of Sunday 30 May again on Hay Player