United States Yacht Shows will be holding the premier showcase for large luxury yachts between June 5 and 8 at National Harbor in Oxon Hill. The show will feature only discriminating yachts of imposing size to be displayed in the new marina at National Harbor on the Potomac. Yachts will be available for purchase or worldwide charter. On land may be found only the most impeccable of yacht launches and tenders, said a spokesman for the show.  Tents and land space will feature an abundance of exhibitors providing equipment, services and materials for the type of yachts displayed. Displays will include engines, electronics, propulsion systems, interior design, yacht design and construction, maintenance, provisioning and financing. Tours of adjacent historic Alexandria by water or land will also be available as an option to yacht buyers.  The show will be open Thursday, June 5 from 11 am to 6 pm, and on Friday, June 6 from 11 am to 7 pm. On Saturday, June 7, the show will be open from 10 am to 7 pm, and on Sunday, June 8, from 10 am to 6 pm.  V.I.P. tickets are $40, and with this ticket youll receive concierge service, access to the V.I.P. Lounge, light fare with non-alcoholic beverages and a cocktail sample of beer, rum or vodka. Regular Admission tickets are available for $16.