Alma Cottage is a a tea-room and guest-house in Pin Mill run by Miss Powell where the Walkers stay, in (WD1,2,3,14) and (SW1,2).
Miss Powell is based on a real person Mrs Powell, who was born in Alma Cottage when it was the Alma Inn. She learnt to make omlettes after young AR fans wanted omelettes like the mushroom omelettes following pea soup that Jim Brading and his uncle used to telegraph for (WD2). She left it in 1955 (NBUS page 117). Her telephone number (in WD16) is Woolverstone 30.
Ted Walker apparently knows or knows of Miss Powell and Alma Cottage (WD 23), possibly due to his Naval links with colleagues at Shotley.