| PLANAHEAD | Be prepared to map a river's source (4,5) |
| RAPID | Quick swim towards a river's source, heading in northerly direction (5) |
| UPSTREAM | Towards a river's source |
| URN | A jar for the ashes of a person or a burnt cricket bail, for example; a pitcher; an ancient cista for voting-tablets, hence today's ballot box; a footed vase or sculpture; a tea vat with a tap; or, po |
| RHINEALPS | Adapted inhalers requiring pressure to find Swiss river source (5,4) |
| CHARTERED | Sanctioned to map deer out (9) |
| CHARTISTS | Old reformers getting to map out awards from university (9) |
| ORIENTATE | Locate yourself in relation to map |
| LAKETAHOE | Truckee River's source (Chevrolet) |
| BILLABONG | In America check pipe going round a river's offshoot |
| APERTURES | A river's full of fresh openings |
| ESTUARINE | Found near a river's mouth (9) |
| CARD | Item whose metaphorical concealment up one's sleeve pertains to a secret asset/plan kept in reserve until needed; a domino; a map; a meishi; or, a race programme (4) |
| AHEAD | In front of a river source (5) |
| APOGEE | Highest point of a river -source of Ganges (6) |
| PORTSMOUTH | When rambling, sort out map (A to H) to show city (10) |
| OCCLUDEDFRONT | On a weather map, a line with semicircles and triangles |
| KAMPALA | King to map out a city as a capital (7) |
| RELIEF | --- map, a map that shows the configuration and height of the land surface (6) |
| RIVER | Represented as a blue line on an Ordnance Survey map, a natural type of watercourse inhabited by mammals, birds, fish insects and plants (5) |
