What are their opening hours, please?
SELECT Name ,  Opening_Hours FROM TOURIST_ATTRACTIONS WHERE How_to_Get_There   =   "bus" OR How_to_Get_There   =   "walk"
their refers to TOURIST_ATTRACTIONS; opening hours refers to Opening_Hours; accessible by bus or walk refers to How_to_Get_There = 'bus' OR How_to_Get_There = 'walk';