Editing Dual gauge (section)

===Three rails===
[[File:Cross-section of Australian dual-gauge railway track.tif|thumb|left|Configuration of dual-gauge (1600 mm and 1435 mm) track.]]

Constructing dual-gauge track with three rails is possible when the two adjacent rails can be separated at the base by at least the space required by rail fastening hardware such as spikes and or rail clips – typically {{convert|40|mm|in|abbr=off|comma=off}}. If the two gauges are closer than that, four rails must be used. Depending on the rail fasteners used and the weight of rails (heavy rails are bigger), the practicable difference between the two gauges is in the range {{convert|145|mm|in|abbr=off|comma=off}} to {{convert|200|mm|in|abbr=off|comma=off}}.<ref>{{cite book |date=1988 |title=Track Maintenance Guide |publisher=Australian National Railways Commission |location=Adelaide |page=section 9.1}}</ref>

{| class="wikitable floatleft mw-collapsible mw-collapsed" border= "1" style= "width:60%; font-size: 86%; float:left; margin-left:2em; margin-right:2em; margin-bottom:2em"
! colspan="2"| {{larger|''' Gallery: Dual gauge (3 rails)'''}}
|-align="center"
|<br />[[Image: Dual-gauge tracks (1600 mm and 1000 mm) at Belo Horizonte, Brazil(cropped).jpg|border|400x130px|none]]
|<br />[[Image: Wallaroo-dual-gauge-railway-0855.jpg |border|400x130px|none]]
|-align="left" vertical-align="top"
|style="vertical-align: top; width=100"|1600&nbsp;/ 1000&nbsp;mm<br />(5&nbsp;ft 3&nbsp;/ 3&nbsp;ft 3<span style="vertical-align:super;font-size:x-small">3</span>/<span style="vertical-align:sub;font-size:x-small">8</span>&nbsp;in)<br />{{efn-la|Commuter lines near Estação Central, City of [[Belo Horizonte]], Brazil, 2007.}}
|style="vertical-align: top; width=100"|1600&nbsp;/ 1435&nbsp;mm<br /> (5&nbsp;ft 3&nbsp;/ 4&nbsp;ft 8<span style="vertical-align:super;font-size:x-small">1</span>/<span style="vertical-align:sub;font-size:x-small">2</span>&nbsp;in).<br />{{efn-la| Secondary main line, [[Wallaroo, South Australia]], 2008. Such close spacing of two rails is at the limit of possibilities for three-rail dual gauge; if closer, a four-rail configuration must be built.}}
|-align="center"
|<br /> [[Image: Dual-gauge (1435 and 891 mm) track and turnout at Jenny, Sweden.jpg|border|400x130px|none]]
|<br />[[Image:Liberec, Tatranská, výhybka u vozovny.jpg |border|400x130px|none]]
|-align="left" vertical-align="top"
|style="vertical-align: top; width=100"|1435&nbsp;/ 891&nbsp;mm<br />(4&nbsp;ft 8<span style="vertical-align:super;font-size:x-small">1</span>/<span style="vertical-align:sub;font-size:x-small">2</span>&nbsp;/ 2&nbsp;ft 11<span style="vertical-align:super;font-size:x-small">3</span>/<span style="vertical-align:sub;font-size:x-small">32</span>&nbsp;in)<br />{{efn-la|Jenny, Sweden, 2006.}}
|style="vertical-align: top; width=100"|1435&nbsp;/ 1000&nbsp;mm<br />(4&nbsp;ft 8<span style="vertical-align:super;font-size:x-small">1</span>/<span style="vertical-align:sub;font-size:x-small">2</span>&nbsp;/ 3&nbsp;ft 3<span style="vertical-align:super;font-size:x-small">3</span>/<span style="vertical-align:sub;font-size:x-small">8</span>&nbsp;in)<br />{{efn-la|Street [[tramway track]] in [[Liberec#Transport|Liberec]], Czech Republic, 2007.}}
|-align="center"
|<br />[[Image: Dual gauge track (1435mm and 1000 mm), Hakone Tozan Line, Japan (cropped).jpg|border|400x130px|none]]
|-align="left" vertical-align="top"
|style="vertical-align: top; width=100"|1435&nbsp;/ 1067&nbsp;mm<br />(4&nbsp;ft 8<span style="vertical-align:super;font-size:x-small">1</span>/<span style="vertical-align:sub;font-size:x-small">2</span>&nbsp;/ 3&nbsp;ft 6&nbsp;in)<br />{{efn-la| Odawara on the [[Hakone Tozan Railway]], Japan, 2005.}}
|}
{{clear}}