example of such a "turbo" dumbbell interchange, which was formerly a half cloverleaf, can be seen in Jülich, Germany at . There are interchanges similar to dumbbells in which the ramps do not meet the roundabouts at intersections; these more closely resemble bowtie intersections. One such interchange exists at the junction between the Ruta Interbalnearia and Route 35 North near La Floresta, Uruguay (). Dogbone A variation of the dumbbell interchange, often called a dogbone interchange (due to its aerial resemblance to a real or toy dog bone), and sometimes also called a double roundabout interchange, occurs when the roundabouts do not form a complete circle but instead have a "raindrop" or "teardrop" shape. These two raindrop roundabouts are fused together, forming a single "squashed" roundabout. This configuration reduces conflicts between vehicles entering the raindrop roundabouts from the ramps, reducing queueing and delays, compared with the dumbbell interchange. Direct U-turns are not possible, although the movement can be made by circulating around both raindrop roundabouts. An example of a dogbone interchange in the United States is located on Interstate 70 in Avon, Colorado, United States; more compact examples, which show less of the characteristic "dog bone" shape, are located along Keystone Parkway in Carmel, Indiana, United States. Several interchanges similar to those along Keystone Parkway are being built along the new US 31 freeway under construction in northern Indiana. There are some hybrid interchanges of dumbbell and dogbone having one raindrop and one full roundabout. This is made when the roundabout intersects more roads than the cross street and ramps. Some examples are at exit 38 of the N7 road in Groningen, Netherlands (at ); and Ennis Avenue (National Route 1) at Safety Bay Road (State Route 18 / Tourist Drive 202) on the border of the suburbs of Waikiki and Warnbro in the City of Rockingham, Western Australia (at ). A tennis ball interchange resembles a dogbone interchange, with the difference being that right turning movements (in a country where traffic drives on the left) cut through the roundabouts like a regular diamond interchange instead of going around the roundabout. Such a design is found in Perth, Western Australia, between Roe Highway (State Route 3) and Berkshire Road (at ). Tight diamond A tight diamond interchange (TDI), also known as a compressed diamond interchange or a tight urban diamond interchange (TUDI), is sometimes used in areas where there is