return (
      <div>
        <div>
          <Link to="/one">One</Link>
          <Link to="/two">Two</Link>
        </div>
        <Switch>
          <Route exact path="/one" component={One} />
          <Route exact path="/two" component={Two} />
          <Route component={Three} />
        </Switch>
      </div>
    );

return (
      <div>
        <div>
          <Link to="/#one">One</Link>
          <Link to="/#two">Two</Link>
        </div>
        <Switch>
          <Route exact path="/#one" component={One} />
          <Route exact path="/#two" component={Two} />
          <Route component={Three} />
        </Switch>
      </div>
    );