OK. I worked on that a bit and found the solution (iD only) The trouble arises from the distinction that iD (but not Potlatch) makes between lines and areas. While lines can be extended [A shortcut], areas don't. So the question turns to "How to turn a closed line into an area and viceversa". A) Hot How to turn an area into a closed line: < DEPRECATED > *Tricky. Just to keep with the example above, lets say you have an area defined by the nodes A,B,C,...,P,Q but you were interrupted from continuous addition. 1- Choose the area. 2- Choose the node Q. Cut [X]. Now the area has turned a "multipolygon relation" with 2 members: the line K,L,...,P,Q and the line Q,A,B,...,J,K (the fact it cuts at K or any other node is somewhat random) 3- ALERT: NASTY DRAWBACK FOLLOWS. Remove both members and the multipolygon tag. At this point, every other tag is removed, which is undesirable if you are editing already stablished areas with much info but is unimportant if you are just mapping new stuff and have a single "forest" or "farmland" tag or alike. Now you are left with 2 single lines. If you are happy with them, just join them [C]. But to solve your problem: 4- Choose the node A. Cut [X]. 5- Choose the line A,Q. Remove [Ctrl-Backspace]. 6- Choose both the line A-K and the line K-Q [Shift-Click]. Join them [C]. 7- Choose the node Q. Continue adding points [A]. Up to Z and back to A. Now you have a closed line that goes from A back to A through B,C,...,J,K,L,..,P,Q,...,Z,A but iD does not offer you to tag it as an area element such as a lake or a farm. Only roads, fences and any linear stuff. But what follows is pretty easy.* < /DEPRECATED > EDIT: Just set the tag area=no, cut the closed line by the node you want and continue adding points from there. Join back the segments into a single line and set back the tag area=yes or remove it if another tag implies it. B) How to turn a closed line into an area: Easy. Choose the line and edit its tags. Add area=yes. Now iD allows you to tag it again as any usual area. Since this question is actually old, I hope this helps future people reading this post. iD feels very comfortable but some situations like this one must be simplified to actually overcome Potlatch2.

OK. I worked on that a bit and found the solution (iD only) The trouble arises from the distinction that iD (but not Potlatch) makes between lines and areas. While lines can be extended [A shortcut], areas don't. So the question turns to "How to turn a closed line into an area and viceversa". A) Hot to turn an area into a closed line: Tricky. < DEPRECATED > *Tricky. Just to keep with the example above, lets say you have an area defined by the nodes A,B,C,...,P,Q but you were interrupted from continuous addition. 1- Choose the area. 2- Choose the node Q. Cut [X]. Now the area has turned a "multipolygon relation" with 2 members: the line K,L,...,P,Q and the line Q,A,B,...,J,K (the fact it cuts at K or any other node is somewhat random) 3- ALERT: NASTY DRAWBACK FOLLOWS. Remove both members and the multipolygon tag. At this point, every other tag is removed, which is undesirable if you are editing already stablished areas with much info but is unimportant if you are just mapping new stuff and have a single "forest" or "farmland" tag or alike. Now you are left with 2 single lines. If you are happy with them, just join them [C]. But to solve your problem: 4- Choose the node A. Cut [X]. 5- Choose the line A,Q. Remove [Ctrl-Backspace]. 6- Choose both the line A-K and the line K-Q [Shift-Click]. Join them [C]. 7- Choose the node Q. Continue adding points [A]. Up to Z and back to A. Now you have a closed line that goes from A back to A through B,C,...,J,K,L,..,P,Q,...,Z,A but iD does not offer you to tag it as an area element such as a lake or a farm. Only roads, fences and any linear stuff. But what follows is pretty easy. easy.* < /DEPRECATED > EDIT: Just set the tag area=no, cut the closed line by the node you want and continue adding points from there. Join back the segments into a single line and set back the tag area=yes or remove it if another tag implies it. B) How to turn a closed line into an area: Easy. Choose the line and edit its tags. Add area=yes. Now iD allows you to tag it again as any usual area. Since this question is actually old, I hope this helps future people reading this post. iD feels very comfortable but some situations like this one must be simplified to actually overcome Potlatch2.

OK. I worked on that a bit and found the solution (iD only) The trouble arises from the distinction that iD (but not Potlatch) makes between lines and areas. While lines can be extended [A shortcut], areas don't. So the question turns to "How to turn a closed line into an area and viceversa". A) Hot to turn an area into a closed line: Tricky. Just to keep with the example above, lets say you have an area defined by the nodes A,B,C,...,P,Q but you were interrupted from continuous addition. 1- Choose the area. 2- Choose the node Q. Cut [X]. Now the area has turned a "multipolygon relation" with 2 members: the line K,L,...,P,Q and the line Q,A,B,...,J,K (the fact it cuts at K or any ohter other node is somewhat random) 3- ALERT: NASTY DRAWBACK FOLLOWS. Remove both members and the multipolygon tag. At this point, every other tag is removed, which is undesirable if you are editing already stablished areas with much info but is unimportant if you are just mapping new stuff and have a single "forest" or "farmland" tag or alike. Now you are left with 2 single lines. If you are happy with them, just join them [C]. But to solve your problem: 4- Choose the node A. Cut [X]. 5- Choose the line A,Q. Remove [Ctrl-Backspace]. 6- Choose both the line A-K and the line K-Q [Shift-Click]. Join them [C]. 7- Choose the node Q. Continue adding points [A]. Up to Z and back to A. Now you have a closed line that goes from A back to A through B,C,...,J,K,L,..,P,Q,...,Z,A but iD does not offer you to tag it as an area element such as a lake or a farm. Only roads, fences and any linear stuff. But what follows is pretty easy. B) How to turn a closed line into an area: Easy. Choose the line and edit its tags. Add area=yes. Now iD allows you to tag it again as any usual area. Since this question is actually old, I hope this helps future people reading this post. iD feels very comfortable but some situations like this one must be simplified to actually overcome Potlatch2.

OK. I worked on that a bit and found the solution (iD only) The trouble arises from the distinction that iD (but not Potlatch) makes between lines and areas. While lines can be extended [A shortcut], areas don't. So the question turns to "How to turn a closed line into an area and viceversa". A) Hot to turn an area into a closed line: Tricky. Just to keep with the example above, lets say you have an area defined by the nodes A,B,C,...,P,Q but you were interrupted from continuous addition. 1- Choose the area. 2- Choose the node Q. Cut [X]. Now the area has turned a "multipolygon relation" with 2 members: the line K,L,...,P,Q and the line Q,A,B,...,J,K (the fact it cuts at K or any ohter node is somewhat random) 3- ALERT: NASTY DRAWBACK FOLLOWS. Remove both members and the multipolygon tag. At this point, every other tag is removed, which is undesirable if you are editing already stablished areas with much info but is unimportant if you are just mapping new stuff and have a single "forest" or "farmland" tag or alike. Now you are left with 2 single lines. If you are happy with them, just join them [C]. But to solve your problem: 4- Choose the node A. Cut [X]. 5- Choose the line A,Q. Remove [Ctrl-Backspace]. 6- Choose both the line A-K and the line K-Q [Shift-Click]. Join them [C]. 7- Choose the node Q. Continue adding points [A]. Up to Z and back to A. Now you have a closed line that goes from A back to A through B,C,...,J,K,L,..,P,Q,...,Z,A but iD does not offer you to tag it as an area element such as a lake or a farm. Only roads, fences and any linear stuff. But what follows is pretty easy. B) How to turn a closed line into an area: Easy. Choose the line and edit its tags. Add area=yes. Now iD allows you to tag it again as any usual area. Since this question is actually old, I hope this helps future people reading this post. iD feels very comfortable but some situations like this one must be simplified to actually overcome Potlatch2.