Hi ColinThank you.SRTMfill works wonderfull. I will try Microdem later.By now I will stay with my script. I successfull merged 12 tiles (3 x 4) into one and have now an area from 46N 14E to 49N 18E, which covers the east of austria. I have to rework some airports, than I will upload this data.happy new yearHarald

Many thanks. I have checked the "make pod" but I havn't been sure of the processes it asks for and cancelled out.ie name file,volume etc.I assume when editing strm files for America that I should use 3601 for the length and height. Are there any other changes from those used with 1201 strm that I should make to the scenery import window.Richard.

Rich,The filename is whatever you choose.The volume name is largely irrelevant - you can put what you like there. Normally 'created by Rich Press' or something similar. As for the US dems, yes just change the data size, the area will be the same. You will almost always need 4 srtm files to cover 1 globe tile. You might get away with 2 in some places depending on the latitude.There's a free program called MicroDem that will merge the data sets for you into one big file, then you will have 7201 x 7201.Note: NOT 7202 x 7202 because the adjoining values are the same coordinates and same value.Colin