Posted By Stuart Nagle Hi, Adam. I need some further information before I can really respond in detail, however, for what you have indicated thus far: 1) netlon in its various forms may be a geotextile membrane employed within civil engineering to improve the structural stability of soils in respect of their bearing ratio(they can carry heavier loads) or used in retaining earth embankments. As far as I am aware it is not generally used as the wearing surface for cars to park on, in a field or any other area where the surface needs to be maintained. In such cirumstances, usually either a plastic or concrete geo-grid structure is used, which then has turf, soil or other (perhaps granular) fill materials laid over it and compacted into the 'geo-grid'. Sopme types of this surfacing, partularly the plastic types, are interlocking on all sides, to provide further structural stability. The general idea being that the loads applied, such as when vehicles pass over, is spread over a wider area giving greater stability and preventing bog down and/or maintaining a surface such as a grassed area. from experience, I can advise that the plastic geogrids are very slippery in wet weather, when plastic edges of the geoblocks become exposed. This occurs after the infill that has been insitu for a while, settles or has been over-run for a period of time. During my career in Highways Engineering and maintenance I dealt with several insurance claims arising from trips, slips and falls on this material, where it had been installed to allow off-street parking on grassed areas in roads that were very narrow. Conrete is by far the best option. It does have certain disadvantages however. 1) it is far more expensive that the plastic material (the plastic materials are usually recycled) 2) the contours of the concrete geoblocks are thicked and therefore more obtrusive 3) the units require a greater degree of labour and more preparation of the formation in order to be installed. This is why a lot of plastic now infests grassed areas !! Treatments: Plastic and concrete will require infilling where they are subject to heavy trafficking. remeber these were originally designed to enable areas to cope with just ocassional use for loads !! Plastic will always be slippery, particularly when wet. there is little that can be done here. Concrete is by far more user frendy here and whilst not slippery, will provide the trips, as plastic does. Gravel is not a good idea. Whilst mechanical interlock of the gravel may be achieved, it will, under load, eventually kill the plastic geoblocks through abrasion. A DOT Type'1' material (with lots of fines) or a coarse sand may be better if you must infill the area at all. Grass infilling of course will mearly create more problems, such as mud and further compaction leaving you where you started. Hope this helps... Regards... Stuart Nagle