A detailed world map of submarine cables provided by telegeography.com
No particular part or subset of the Internet traffic to or from Switzerland is routed via the United Kingdom specifically.
Switzerland is a landlocked country, with France, Italy, Germany, Austria as its biggest neighbors. The Internet in Switzerland has direct land-based with ISPs in these countries.
Internet routing itself is a highly dynamic affair. Some routes to and from the United States will go via Iceland, Ireland, Denmark and the United Kingdom, as for most of continental Europe. But this is not the only route, nor does an entirely session go over only one particular route. The degree of variance depends on link costs, bandwidth and latency. More detailed information and some statistics are available from Swisscom and init7. These also show the vast majority of traffic is not traveling via the UK.