From Amazon.co.uk:
It is 1923 and Evangeline English, keen lady cyclist, arrives with her sister Lizzie and their zealous leader Millicent at the ancient city of Kashgar to establish a mission. As they encounter resistance and calamity, Eva commences work on her Lady Cyclist's Guide to Kashgar...

In present-day London, Frieda opens her door to find a man sleeping on the landing. Tayeb, a Yemeni refugee, has arrived in Frieda's life just as she learns that she is next-of-kin to a stranger, a woman whose abandoned flat contains many surprises. The two wanderers embark on a journey that is as great, and as unexpected, as Eva's.

Left at the Little Library.

Release #9 for the 2017 Sapphire Challenge.

Kept me captivated all the way through. A good read.